What was the Apostles' view of eternal life and the soul? How should I grapple with and reconcile myself to the development in time of concepts central to the faith?

Hello all,

Please excuse the healthy dose of theological and scriptural ignorance that is sure to permeate what follows.

I'm a recent revert to the Catholic faith and by the grace of God I'm fully in, body and soul. So much so that I'm in the early stages of discerning the religious life. As far as my heart is concerned, the Catholic Church is the one true Church. My mind, however, is proving more difficult to tame. I'm really rather oblivious to basic theology--my undergrad was in philosophy which has provided a great critical foundation for the study of theology, but also sometimes feels like a critical weapon *against* my theological assumptions.

Something that's troubling me this morning is the concept of the soul. My lay view of the soul, inherited however imperfectly from the Church, is of an immortal essence that outlives the body. Souls are what we are, deep down. The soul and its fate are what's at stake in this life. However, having done a cursory study of the history of the concept, I see that its origins are something of a fusion of Platonic and Jewish ideas, and that the concept as we now understand it really cannot be clearly located in scripture. Apparently, it was centuries after the death of Christ that the Church had settled on an interpretation (having ruled out possibilities like pre-existence and transmigration) resembling what we lay moderns possess.

I find this uncertainty (which lasted literally hundreds of years after the death of Christ) troubling, not least because pretty much the entirety of my understanding of Christ's teachings rests on the notion of the soul that I inherited from culture, and from the Church. Absent a modern view of the soul, what did the Apostles, for instance, believe Christ meant when He promised them eternal life? Did they imagine that they too would rise, as He did, physically, from the dead, and be assumed like Mary? How am I to deal with the historical uncertainty and development in time of this central concept, which I assume is not unique in having such a history?

Thank you for reading, and for your time. God bless you!