The effectiveness of religion

In this post, BenefitOfTheDoubt ranked the most important factors for happiness in this life, taking into account effect size, strength of evidence and directness of evidence. They close with the finding that the impact of religion on individual happiness is dwarfed by material considerations. 

To illustrate, recent longitudinal studies which isolate within-person change find that while more religious people tend to report higher life satisfaction on average, increases in a given individual’s religiosity do not reliably predict later increases in their own life satisfaction (nor vice-versa). For example, Joshanloo (2021) found positive between-person associations but no significant within-person cross-lagged effects over 20 years in U.S. adults and Prati (2024) similarly reported almost no within-person lagged effects of religion on mental health in a large German panel.

However, science cannot address the question of what, if anything, happens to our subjective experience after death, because the scientific method is restricted to observable outcomes and even discovery of the neural correlates of consciousness cannot bridge the mind-body gap or problem of other minds. Setting aside what religion is effective for in this life, what can reason and evidence suggest about what will give us the “happiest” afterlife?

This question is important, because a considerable portion of the population hold to beliefs that imply that the afterlife carries far more utility than anything in this life.

Pascal’s wager

Pascal’s Wager frames that unknown with a cost-benefit analysis: if God exists, belief can result in a great reward in the afterlife; if God does not exist, the cost of belief is small. If you assign a probability of god’s existence as zero or infinitismally small, even a million utility reward multiplied by 0 probability is still zero. However, supposing as many claim infinite reward against even a tiny probability has high expected value. 

Many god’s objection

A major objection to Pascal's wager is the “many-gods objection,” which points out that different religions posit different deities, salvation rules and punishments (see Saka 2001; Jordan 1993). The decision is thus not between belief and unbelief but among several incompatible options with uncertain pay-offs.

To resolve this objection, Askell (2018) suggests beginning with a ranking that assigns higher initial probability to better-supported religious hypotheses. Building on that idea, I propose three filters to narrow the field: first, consensus of authority, giving more weight to the authority (such a historical source quoting Jesus closer to the time of his life may be more authoritative than later claims in the Christian tradition) that is endorsed by the largest populations; second, coherence of criteria for heavenly reward as articulated by that authority - noting that another major challenge is that belief is not a sufficient criteria for reward in the afterlife in the major world religions. The final filter is correspondence of that reward with what humans would understand as hedonically rewarding (euphoria, absence of pain etc); taking into account the magnitude of stakes, concentrating on claims that promise outsized reward or punishment. As you will see below, these filters leave a small set of beliefs that appear maximally consequential for maximising utility in the afterlife.

Internal contradiction with the religions traditions reviewed, or external contradiction with the sciences and historical scholarship, where it does not relate to claims about the afterlife, are ignored for the purposes of this analysis. By analogy, a scientific paper can include a mistaken anecdote and still prove a valid theorem on a different page when the proof does not rely on the error elsewhere.

Consensus

Remarkably, over half of humanity, approximately 4.4 billion individuals or 55% of the global population - worship the “same” Abrahamic God recognised Christianity, Islam, and Judaism. Despite theological differences, these religions trace their heritage to the same deity they believe was revealed to someone named Abraham. It is believed this deity is a fusion of two deities worshipped as part of a pantheon in pre-Jewish Israelite religion. 

Christianity (approximately 31%) explicitly identifies this connection to the God of Abraham in verses such as, "the God of Abraham, the God of Isaac, and the God of Jacob" (Matthew 22:32), and Paul's assertion, "If you belong to Christ, then you are Abraham’s seed" (Galatians 3:29). Islam (approximately 25%) similarly affirms shared worship: "Our God and your God is One" (Qur’an 29:46). Judaism (approximately 0.2%) consistently describes God as "the God of your fathers, the God of Abraham, Isaac, and Jacob" (Exodus 3:15). Thus, most believers in these faiths understand themselves as worshipping the same singular Creator, despite variations in interpretation and practices.

Had I lived at certain points in ancient Rome, the Roman pantheon might have seemed most prevalent. In contrast, Christianity is currently the world’s largest religion, and Islam is projected to surpass it by the end of the century. My analysis is however necessarily grounded in the present historical context that we, the reader and I, actually inhabit. Moreover, because populations have grown, the number of persons attesting to these religions is greater than the number of people who have attested to any religion at any one point in the past. This is considered in establishing the consensus view.

But this is also not to say there aren't secular interpretations for why some religions spread more than others. Some have argued that it is for Christianity and Islam the relative focus on exclusivity, proselytisation and charity that facilitated their spread. Even granting these factors, the question remains, why these two religions in particular?

Judaism did not spread widely, whereas Christianity evidently did. Widely recognised Agnostic atheist bible scholar Bart Ehrman confesses that recorded reasons people gave for converting in the spread of early Christianity was that miracles performed in the name of Jesus miraculously appeared to be more powerful than those performed in the names of pagan gods. The miracle, or rather, collection of miracles attributed to Christianity, could be interpreted as evidence of historical efficacy of prayer. However, as we see, the evidence for religion on well-being today in this life appears muted. 

Other factors that have been commented upon by others as factors in Christianity’s virulence are exclusivity (monotheism) which made it outcompete polytheism, and that Christianity unlike Judaism pivoted to a focus on conversion. In contrast, Judaism, the oldest monotheistic religion, not have a focus on conversion. Islam was similarly monotheistic, and focussed on conversion, and also experienced significant spread. Monotheism appears to be the exception historically around the world so that is an alternative secular explanation for why these innovations both happened to come out of the middle east. Historically, Muhammad was aware of Christianity and acknowledged Chrisitniaty and Judaism in his time. 

Contention

Mainstream Christianity teaches that salvation is available only through faith in Jesus Christ as the divine Son of God (Nicene Creed). Islam, on the other hand, insists that salvation requires belief in Allah, acceptance of Muhammad as His final prophet, and rejection of Jesus’ divinity: 

Qur'an 5:72: "They have certainly disbelieved who say, 'Allah is the Messiah, the son of Mary,' while the Messiah has said, 'O Children of Israel, worship Allah, my Lord and your Lord.' Indeed, he who associates others with Allah – Allah has forbidden him Paradise, and his refuge is the Fire. And there are not for the wrongdoers any helpers."

This highlights a critical point of divergence: Mainstream Christianity and Islam present mutually exclusive paths to a favourable afterlife. The Pew Research Centre says about half of Christians are Catholic. Protestants, broadly defined, make up 37%. Orthodox Christians comprise 12% of Christians worldwide. 

Thresholds

You can skip over this section if you just want to follow the logical argument, rather than the excursion into the theological that follows:

Information hazard about learning more about Islam and Catholicism

Islamic theology holds that accountability before God depends on the clear and accurate communication of the divine message. As the Qur’an states, “We never punish until We have sent a messenger” (17:15), indicating that individuals are only held fully accountable once the message of Islam has been unmistakably conveyed to them.  To note, Muhammad in his life did not seem focused on converting Jews and Christians, perhaps because they worship the same god. 

There is a comparable information hazard for Catholicism. I do not know this to generally apply in most Protestant traditions. 

Criteria for salvation in Christianity 

There appears to be broad consensus across major traditions in support of certain criteria for salvation in Christianity:

• Jesus said, “Whoever believes and is baptized will be saved” (Mark 16:16). And, “No one can enter the kingdom of God unless they are born of water and the Spirit” (John 3:5). And “He saved us through the washing of rebirth and renewal by the Holy Spirit” (Titus 3:5).
• Romans 10:9 affirms, “If you declare with your mouth, ‘Jesus is Lord,’ (note that Lord does not necessarily translate to God) and believe in your heart that God raised him from the dead, you will be saved.” However, this faith must be sincere and transformative. Jesus warns, “Not everyone who says to me, ‘Lord, Lord,’ will enter the kingdom of heaven, but only the one who does the will of my Father” (Matthew 7:21). Salvation is not secured by a one-time event but by a continuing life of faith. Jesus said, “The one who stands firm to the end will be saved” (Matthew 24:13),
• The Apostle Paul, in 1 Corinthians 6:9-10, writes: “Do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived: neither the sexually immoral, nor idolaters, nor adulterers, nor men who practice homosexuality, nor thieves, nor the greedy, nor drunkards, nor revilers, nor swindlers will inherit the kingdom of God.” Likewise, Revelation 21:8 offers a sobering list of those who persist in grave sin without repentance: “But as for the cowardly, the faithless, the detestable, as for murderers, the sexually immoral, sorcerers, idolaters, and all liars, their portion will be in the lake that burns with fire and sulfur. In Romans 14:23 (ESV) Paul teachers “For whatever does not proceed from faith is sin”.
• Matthew 25:41-46 NIV: ⁴¹ "Then he will say to those on his left, 'Depart from me, you who are cursed, into the eternal fire prepared for the devil and his angels. ⁴² For I was hungry and you gave me nothing to eat, I was thirsty and you gave me nothing to drink, ⁴³ I was a stranger and you did not invite me in, I needed clothes and you did not clothe me, I was sick and in prison and you did not look after me.' ⁴⁴ "They also will answer, 'Lord, when did we see you hungry or thirsty or a stranger or needing clothes or sick or in prison, and did not help you?' ⁴⁵ "He will reply, 'Truly I tell you, whatever you did not do for one of the least of these, you did not do for me.' ⁴⁶ "Then they will go away to eternal punishment, but the righteous to eternal life."

Additionally to the above, there are a number of practices which are contested. For example Catholics believe the eucharist is ordinarily necessary for salvation whereas a number of Protestant traditions consider it idolatry.

Criteria for salvation in Islam

The Qur’an presents a nuanced perspective on the fate of non-Muslims. Verses such as 2:62 and 5:69 affirm that Jews, Christians, and Sabians, who believe in God, the Last Day, and act righteously - may attain salvation. These verses suggest that righteousness and sincere belief can lead to God's mercy, even outside the formal bounds of Islam.

The Qur'an presents a path to Paradise in the verse: "Indeed, those who have believed and done righteous deeds – they will have the Gardens of Paradise as a lodging." (Qur'an 18:107). 

Surah Al-Ma'idah (5:72) of the Qur'an says "Indeed, he who associates others with Allah, Allah has forbidden him Paradise, and his refuge is the Fire…”

The Quranic shahada is the foundation of Islamic belief (Quran 3:18). The Quran presents a clear and singular form of the shahada: "Ash hadu an lâ ilâha illâ Allah" (“I bear witness that there is no god but God”). It also warns against making distinctions among messengers (Quran 4:152). It is interesting to note that Jesus would have used the related Aramaic term alaha (ahl-ah-HAH) to speak of God. The Arabic Allah derives from the same Semitic root

What about the next most popular religions, Hinduism and Buddhism? 

Not only are these religions less popular worldwide than the Abrahamic religions, in the Bhagavad Gita, in verses 7:23, Krishna explains “Men of small intelligence worship the demigods, and their fruits are limited and temporary. Those who worship the demigods go to the planets of the demigods, but My devotees ultimately reach My supreme planet.” (per the Hare Krishna translation) or “But finite is the result gained by these men of small minds. Those who worship the deities go to the deities; those who worship Me come to Me” in the Advaita Vedanta translation. While translations vary based on the school of thought in Hinduism that translated these texts, a Christian who prays to God the Father or a Muslim who devoutly submits to Allah may still find a good outcome if Hindu beliefs are correct.

Buddhism, especially in its earliest contemporary form (Theravāda), does not teach eternal heaven or hell. "Do not go upon what has been acquired by repeated hearing; nor upon tradition; nor upon rumor… But when you know for yourselves that, ‘These things are wholesome; these things are blameless; these things are praised by the wise; undertaken and observed, these things lead to benefit and happiness’ — then enter on and abide in them.". In the most common form of Buddhism today - Mahāyāna Buddhism, especially as practiced in East Asia (e.g., China, Japan, Korea, Vietnam) - the idea of liberation or rebirth in a "pure land" can involve faith in certain buddhas (like Amitābha), but this faith is not restricted by sectarian boundaries. Even here, the emphasis is more on sincere intent, compassion, and wisdom than institutional identity. A well-known Mahāyāna scripture, the Lotus Sutra (Saddharma Puṇḍarīka Sūtra), expresses this openness clearly:> "All beings, whether they have faith or not, whether they practice this teaching or not, whether they slander it or praise it - all shall eventually attain Buddhahood." - Lotus Sutra, Chapter 2

Criteria for salvation in Judaism

Judaism, as the theological foundation of both Christianity and Islam, raises a distinctive question when considering salvation for non-Jews. Unlike Christianity or Islam, Judaism does not universally require conversion for salvation. Instead, it holds that non-Jews may attain a share in the World to Come (Olam HaBa) by adhering to a basic set of ethical principles known as the Noahide Laws. These include prohibitions against murder, theft, idolatry, sexual immorality, blasphemy, and cruelty to animals, along with a requirement to establish systems of justice. These laws are widely reflected in the moral norms of many societies today.

Mainstream rabbinic Judaism including nearly all contemporary Jewish denominations affirms that righteous individuals of all nations can merit salvation without becoming Jewish. This is explicitly stated in the Talmud:

"The righteous of all nations have a share in the World to Come." - Tosefta Sanhedrin 13:2; Babylonian Talmud Sanhedrin 105a.

Islam vs Christianity: Should you believe Jesus is God? 

As stated earlier, there is contention between the threshold for salvation between Islam and Christianity. The question between those faiths is not whether to believe in the God of Abraham, but whether Jesus “is” the God of Abraham? 

In the canonical New Testament Gospels, Jesus never explicitly claims to be God nor instructs followers to worship him directly. Instead, he is ambiguous. For instance, Mark 14:36: “Abba, Father, all things are possible for you. Remove this cup from me; yet not what I will, but what you will.”. Mark 13:32 “But about that day or hour no one knows, neither the angels in heaven, nor the Son, but only the Father.” Implication: Jesus admits he does not have divine omniscience, clearly subordinating himself to the Father. On the cross, “My God, my God, why have you forsaken me?” (Mark 15:34) feels like a human prophet crying out, not an all-powerful deity.

So, in the New Testament, Mark the first gospel never has Jesus saying he’s God. It’s only in John, written way later, that you get lines like “I and the Father are one” (John 10:30). Paul calls him “declared Son of God” after the resurrection (Romans 1:4), but “Son of God” was a title for holy humans in Jewish tradition, like kings or prophets (Psalm 2:7), not a claim to being God.

What do I mean by later? Most scholars agree the Gospels were not written by the apostles themselves. They were written decades after Jesus' death, not during his lifetime. The Gospel of Mark came first, around 65–75 CE, followed by Matthew and Luke around 80–90 CE, and John around 90–110 CE. The real apostles were Aramaic-speaking Jews from rural Galilee, unlikely to have written such works in Greek. 

Based on historical evidence, the Gospels do not appear to be written during Christ’s life, but later, and the earliest Christian sources appear to be Paul’s letters, who never met Jesus in person but did meet apostles and had animosity with them, for some of them including Jesus's brother wanted not to spread Christianity to the non-Jews whereas Paul did. This makes me wonder if Jesus would have wanted Christianity to spread to those not born into judaism, because his earliest interpreters weren't so sure.

It is important to note the Gospels named after Apostles are actually anonymous and do not inside themselves claim to be written by the apostles they are named after nor from the perspective of the apostles. The Gospel of Mark is not automatically more reliable than the Gospel of John, just as a biography of John F. Kennedy written during his lifetime is not necessarily more trustworthy than one written decades later. Reliability depends on a number of factors, not simply on when the text was composed. However, Jesus only claimed to be god in the last gospel, john, so that’s not corroborated by the remaining three earlier gospels

The mainstream academic view is that Matthew and Luke both copied from Mark and likely another source of sayings ("Q"), showing they were compiling existing traditions rather than writing from firsthand experience. John’s Gospel shows the most theological development, with ideas like Jesus as the eternal Word (Logos), which were not present in early preaching.

Because Mark is the earliest, least polished, and lacks later theological layers, many historians consider it the most reliable starting point for understanding the historical Jesus. It reflects fewer later church doctrines and preserves a more raw, ambiguous portrayal of Jesus than the later gospels.

Early Christians did call Jesus kyrios (Greek for "Lord"), however the term was used for both secular authorities ("master") or divinity ("God"). The Council of Nicaea in 325 CE long after Jesus sought to settle these ambiguities by affirming Jesus's divinity and equality with God the Father, formalising Trinitarian theology. However, before Nicaea, Christian beliefs were highly diverse: some communities saw Jesus as fully divine, others as subordinate to God, and still others primarily human. 

Magnitude of stake - Christianity

If one religion claims an afterlife that is much better than another, that could up it’s expected value.

In the Gospel of Mark, the good afterlife is referred to as "the kingdom of God" or "life," but it is not described in emotional or experiential terms. Its value is emphasized through comparison and warning e.g:

"it is better for you to enter the kingdom of God with one eye than to have two eyes and to be thrown into hell, where their worm never dies, and the fire is never quenched." Mark 9:47-48 where Jesus is quoting Isaiah: "And they shall go out and look at the dead bodies of the people who have rebelled against me; for their worm shall not die, their fire shall not be quenched, and they shall be an abhorrence to all flesh.".

Mark implies the desirability of salvation but offers no description of its content. In contrast, hell is depicted with strong visual metaphors:

“To go into hell, to the unquenchable fire… where their worm does not die, and the fire is not quenched.” (Mark 9:43–48)

There is no elaboration on the experience of the saved or the condemned beyond these metaphors.

The concept of "Heaven" has roots in Greek thought and was later adopted by early believers when it became clear that Jesus was not returning within their lifetimes. In the Gospel of Mark, Jesus appears to distinguish between the Kingdom of God, depicted as an internal, present reality, and the Resurrection, a future event tied to the return of Jesus.

Pascal’s Wager (17th century) reflects later developments. Pascal assumes the infinite bliss of heaven and infinite torment of hell because by his time, those were well established in later Catholic writing,

Magntitude of stake - Islam

In the Qur’an, the good afterlife, Jannah, is depicted in terms of feeling and satisfaction.

“Indeed, the righteous will be amid gardens and springs. [It will be said], ‘Enter it in peace, safe and secure.’ And We will remove whatever is in their hearts of resentment — [so they will be] brothers, on thrones facing each other. No fatigue will touch them therein, nor from it will they ever be removed.” (Qur’an 15:45–48)

“Indeed, those who say, ‘Our Lord is Allah’ and remain steadfast - the angels will descend upon them [at death], saying, ‘Do not fear or grieve, but receive good news of Paradise, which you were promised. We were your companions in worldly life and [so will we be] in the Hereafter. You will have whatever your souls desire and whatever you request - a welcome gift from the Most Forgiving, Most Merciful.’” (Qur’an 41:30–32)

“Allah has promised the believing men and believing women gardens beneath which rivers flow, where they will live forever, and beautiful homes in Gardens of Eternity. But the greatest reward is the pleasure of Allah — that is the ultimate success.” (Qur’an 9:72)

The bad afterlife, Jahannam, is described through physical punishment and emotional responses:

“They will wish to get out of the Fire, but never are they to emerge therefrom; and for them is a lasting punishment.” (Qur’an 5:37)

“Indeed, the criminals will be in the punishment of Hell, abiding eternally. It will not be allowed to subside for them, and they, therein, are in despair.” (Qur’an 43:74–75)

In the Bhagavad Gita, the good afterlife is liberation from rebirth is the misery of this world.

“Having attained Me, the great souls are no longer subject to rebirth in this miserable world, because they have reached the highest perfection.” (Gita 8.15)

The bad afterlife is presented as continued rebirth into unclear circumstances.

"These hateful, cruel, and vile people—the lowest of humanity—I repeatedly cast into demonic wombs, in the cycle of birth and death." (Gita 16.19)

“Bewildered by false ego, strength, pride, lust, and anger… they fall into the unclean worlds of hell.” (Gita 16.18–20)

These states are described morally and spiritually, but not affectively, there is no direct description of how they are emotionally experienced by the soul.

Unlike later Hindu scriptures such as the Bhagavad Gita or Upanishads, which focus on liberation (moksha), the good afterlife in the Vedas is commonly described as reaching Svarga (heaven), particularly through the performance of correct rituals and sacrifices, and by living a life in accordance with dharma.

 “Where there is eternal light, in that world where the sun has set not, all desires are fulfilled — there make me immortal.” Rigveda 9.113.7–11

Instead, those who fail to perform rituals or who act wrongly may fall into lower realms, such as darkness or “bottomless pits,” or simply be excluded from the heavenly path.

 “Let not the fire consume your skin nor scatter your limbs. Let your body be united again and go to those who lead holy lives.” Rigveda 10.16.9

Naraka as a term does not appear in the Vedas - it becomes more prominent in later literature such as the Mahabharata and Puranas.

Atala, as described in the Bhagavata Purana (5.24.7), presents a strikingly different picture of the afterlife compared to more familiar Hindu texts like the Vedas or the Bhagavad Gita. The Bhagavata Purana, composed around the 9th–10th century CE and highly authoritative in Vaishnava traditions, details a layered cosmology that includes Atala, a lower world (Patala Loka) filled not with torment but with seductive pleasure. Here, sorcerer Bala uses mystic powers to create enchanting women who trap souls in cycles of lust and illusion. This version of the afterlife is not a place of punishment in the conventional sense, but a realm where pleasure becomes a spiritual danger, drawing the soul further from liberation. In contrast, the Vedas, particularly the Rigveda, offer a more restrained and ritual-centric view of the afterlife, emphasizing Swarga (heaven) as a temporary reward for virtuous action, while rarely elaborating on hells.

The Bhagavad Gita (c. 2nd century BCE), considered one of the most philosophically central texts in Hinduism, focuses instead on transcending both pleasure and pain through karma yoga, jnana, and bhakti, leading ultimately to moksha (liberation). The Gita explicitly warns against being swayed by heavenly pleasures or fearful of hell, framing both as part of the illusory dualities of samsara.

From a Pascal’s Wager perspective, where belief is seen as a rational bet to avoid eternal suffering, the portrayal of Atala complicates the logic: here, a “hell” offers intoxicating delight, not suffering, showing that in Hindu thought, illusion (maya) can wear both painful and pleasurable masks. Unlike traditions that offer eternal heaven or hell as binary outcomes, Hindu texts. from the Vedas to the Puranas, consistently portray all such realms, whether painful like Naraka or pleasurable like Atala, as impermanent and spiritually binding. True belief, as emphasized in the Gita, is not about securing a better afterlife, but about transcending all desires and fears, aiming for union with the divine beyond the cycles of rebirth.

The Buddhist Dhammapada describes both the good and bad afterlives using clear emotional terms. Nirvana is associated with bliss, contentment, and peace.

“The evil-doer grieves here and hereafter; he grieves and suffers when he sees the evil of his own deeds.” Dhammapada 15

“The liar goes to the state of woe… he burns in hell.” Dhammapada 306

“He who torments the innocent will soon come to one of these ten states of suffering… being born in hell, in the animal world, in a ghost realm, in poverty, in disease, in madness, or destruction.” Dhammapada 137–140

"Some are born in a womb, evildoers go to hell, the virtuous go to heaven, and those free from defilements attain Nirvana.” Dhammapada 126

"Here he rejoices, hereafter he rejoices. The doer of good rejoices in both worlds. He rejoices and exults, seeing the purity of his deeds.” Dhammapada 18 (Verse 19)

However, the case for good afterlife is undermined for those who do good in this life but remain miserable in this life.

"Even here he is happy, and after death he is happy - the one who has done good." Dhammapada 22 

In the Jewish Tanakh, the emotional quality of the afterlife is described. The clearest is found in Daniel.

“Many of those who sleep in the dust of the earth shall awake, some to everlasting life, and some to shame and everlasting contempt.” Daniel 12:2

There is no elaboration on what “everlasting life” entails. heol in most of the Tanakh is a shadowy, neutral abode of the dead, neither bliss nor torment.

Among these scriptures, the Qur’an and the Hindu scriptures gives the most compelling account of both the good and bad afterlives. 

It is curious that good and bad afterlives feature across conception of the more popular world religions. That may be because it’s a factor in their virulence, or because of the influence of certain early competing religions, perhaps Zoroastrianism or Greek religion.

Conclusion

That’s as far as I've got. I don't know what to conclude from this, or what recommendations fall out of this exploration, but I invite kind comment and discussion.