How does the concepts of soul differ in Stoicism and early Christianity?
For early Christians, the soul was incorporeal, and represented a fusion of the mental and spiritual, It survived after death. At some distant (unspecified) time in the future after the death of Jesus, there would be a "Last Judgement" in which people, granted new incorporeal bodies would be assigned to eternal bliss (Heaven) or eternal punishment (Hell).
For Stoics, the soul was corporeal. It was the seat of individuality and thought. After death, some Stoics believed that the souls of most people would dissipate back into their material components and no longer have individual identity, but the souls of the wise might cohere and persist until the conflagration.