The Summa of Saint Thomas Aquinas, Prima Pars, Question 75 covers the framework of what I'm asking here, but I'm not sure that I'm able yet to wrap my mind around what the Angelic Doctor wrote. In what way are we agentive beings during our mortal lives?

If I had to explain it to children, maybe I'd use the metaphor of how the diaphragm works upon the lungs to bring oxygen into the body. The diaphragm is like the will, and when it functions best, it acts continuously upon the lungs (nature) in order to bring in oxygen (grace). When the will misbehaves, nature does not make enough room for grace, and when the will mends its ways, it purposely acts upon nature to be more open to grace. The problem I see with this metaphor is that the everyday default sounds like the heresy of Quietism, and also it doesn't really answer the question of human agency in a way that includes the soul.

Our Lord taught in parables and some of the best priests tell us to read the saints as role models for how to live. It then happened that the idea popped into my mind of the Holy Family. Is it accurate to say that the will works best by imitating Saint Joseph in his relationship to the Holy Infant as the soul and to Our Blessed Mother as nature perfected by grace? Is this a theologically sound way to think about these questions?

Lastly, can anyone recommend anything to read that is more detailed in application but still clear, practical, and traditionally Catholic (not from someone like Ripperger). Thank you in advance.