One of the reasons I write is to help me think through things.
I often write out ideas in order to get them in order, then throw away the writing and speak extemporaneously. I can speak well because I have written first.
In that spirit, I offer you this, which I just wrote and don't wish to lose quite yet.
At least, not until I have it more firmly in my thick skull.
Saving grace is a free gift from God which we can do nothing to merit, and which God gives freely to us. But, once we receive it, our whole being must necessarily respond to it. So, our mind responds to grace with faith, our body responds with works.
In liturgical theology, both faith and works are responses to grace.
Non-liturgical theology (such as Reformation theology) would say that the mind responds to grace with faith, and then the body responds to faith by exhibiting the fruits, which are works.
The difference is subtle, but profound. Liturgical Christians see human beings as having a two-fold direct response to grace, a mind-body response that is simultaneous. Non-liturgical Christians say there is only a one-fold response to grace: mind alone. Works are a response to faith, not grace.
Thus, in liturgical theology, man's works can actually participate in the life of grace directly, our whole being can participate in the very great promise of God, our whole being can be sharers in the divine nature.
In non-liturgical theology, only your mind can share in the divine nature; the works of the body, being a secondary response and not a primary response, do not share in the divine nature.
Heaven is living a total response to the divine nature.
So, Catholics believe we can live heaven on earth (thus, the Catholic saints), while non-Catholics don't believe that. Our understanding of what the resurrection of the dead means is much more profound as a result.