Please ignore my last comment on 1 cor 3:15 in the above post...i was thinking of something else...
That is a misinterpretation of my comment. Of course we are cooperating with God; otherwise we're doing nothing. Nonetheless, the most important action is God's: "For God is at work in you, both to will and to work for His good pleasure."
A symbolic illustration might be our cooperation in procreation: my husband and I participate with God in producing a child who is biologically a unique genetic issue of the two of us, as well as a unique soul individually created by God. All of us are necessary for the child to be conceived, but God's action is the more "active," as it were, since the human part is done without our conscious effort or ability to achieve the outcome.