I suppose one must firstly divide the Monotheistic Religions - Judaism, Christianity, Islam - from the non-monotheistic, who may believe in an Impersonal Life Force or transpersonal gods or no god - the Eastern religions of Hinduism, Buddhism,etc. Indeed in some instances Buddhism can be described as an atheistic religion.
Hinduism and Buddhism both share the belief in reincarnation (Buddhism, unlike Hinduism, does without the caste system): that the soul wanders in an almost endless cycle of births and rebirths until one is released (having gained good karma) to moksha or nirvana in Buddhism. In Christianity we have a theodicy to explain evil, but the Eastern religions believe that if one suffers in their current lifetime this is because they did bad actions indeed in a past life. Simply put, the epileptic or paraplegic or the blindman is simply suffering for the bad he did in a past life. As Christians, we don’t believe in past lives or that one suffers on account of anything of the sort. The most difficult for the Christian may be accepting that Hindus and Buddhists accept that one may come back as a monkey, a knat, a rat, even an inanimate object in their next life. Even animals have potential Buddhahood and aim for nirvana. That’s why some sects like the Jains even cover their mouths in clothing for fear of swallowing a knat - a perhaps distant relation in a past life. I realize I’m condensing things.
Vis-a-vis the Jews we of course believe in Christ as son of God and that there is original sin, which the Jews don’t believe in. The Jews tend to focus more on the here-and-now, as opposed to the afterlife (little mention of it in the Tanakh- Old Testament). Vis-s-vis Islam, we have a theology of redemption and believe in a Personal Loving Relationship with God, whereas in Islam, God may be called many beautiful names, but ultimately, according to the Venerable Pope John Paul II, he is not Immanuel, God with us, but a God outside of His creation who demands submission.
What sets us apart is our unique theodicy [the Cross], belief in the Trinity, belief in the Incarnation, that God is a Personal Being and One, and not impersonal or polytheistic, among others. Well, O.K. this is obviously from my Christian perspective. I will accept criticism if this is too simplified but I’m tired.
