Although in modern times we synonymize faith with religion, are they really the same thing?
If faith is belief in some particular revelation, and revelation includes a fact that makes eternal happiness more likely than not, what is this fact that faith is based on for other (non-Christian) religions?
For Christianity, that fact is the Resurrection. Is there any comparable event for other religions that requires belief?
Judaism does not require a belief in a particular event for salvation. It is a collection of laws that must be followed. Islam requires belief that Muhammad is the final Prophet and the Quran is the Word of God, but there is no particular event that makes the prospect of eternal happiness more or less likely for the Muslim, as one is judged according to one’s deeds, and the good deeds must outweigh the bad. Zoroastrianism is based on the teachings of Zoroaster but similar to Islam there is no particular revealed event that serves as the basis for faith.
For Indian/Dharmic religions/philosophies, such as Hinduism, Buddhism and Jainism, there is no such thing as eternal happiness. Taoism and Confucianism are performative and do not require faith as a means of attaining eternal happiness. Ancient and folk paganism (or neopaganism) are essentially cultural customs and did not require faith in some revealed fact that gave hope for an eternal reward.
Is Christianity unique in its requirement for faith in a fact? Or do different religions just require faith in different facts?
If my understanding of other religions on this point is inaccurate, please correct.