It’s always fun for me to read your threads. Your mind heads places mine has also - only thing is, mine went there quite a few years ago! Have a feeling I may be a lot older than you. So, before I get to Aquinas, just some thoughts that long ago helped me to accept that this particular question was never going to get answered in the complete way my mind sought.
When we speak of grace (sanctifying), we are speaking of **“life”, **spiritual/supernatural life. So, to try to understand where and how it is contained in something, passed on, received, is difficult - impossible might be closer to it!
I thought just of physical **“life”. **It is :contained" in our physical bodies. It is brought there through the presence of our immaterial soul. Exactly “how” does the soul impart physical life into the physical components of our bodies? Just what “IS” that life? (Not what it does, but what is it?) We can’t even understand questions that fundamental at the physical level, so it’s not surprising we can’t at the spiritual.
Re Aquinas: (I’m adding in brackets the sacramental connect to the analogy)
I don’t know if you read the sections prior to Article 3. I would have done better to connect you to Article 1 - it’s a little more understandable. You asked about the “mechanics” of grace; “How does it work”. Well, you probably never will get that question answered to your satisfaction, but I liked the analogy Aquinas gave in Article 1 regarding the connection of grace to the sacramental matter.
Quote:
Reply Obj. 2** An instrument (sacrament) has a twofold action; one is instrumental (imparts grace), in respect of which it works not by its own power but by the power of the principal agent (God): the other is its proper action [eg. water poured on body, cleans} which belongs to it in respect of its proper form: thus it belongs to an axe (the instrument) to cut asunder by reason of its sharpness, but to make a couch, in so far as it is the instrument of an art. But it does not accomplish the instrumental action save by exercising its proper action: for it is by cutting that it makes a couch. In like manner the coporeal sacraments by their operation, which they exercise on the body that they touch, accomplish through the Divine institution an instrumental operation on the soul; for example, the water of baptism, in respect of its proper power, and thereby, inasmuch as it is the instrument of the Divine power, cleanses the soul: since from soul and body one thing is made. And thus it is that Augustine says that it touches the body and cleanses the heart.
How can we, or can we, obtain grace more effectively, or block it?
We obtain it more effectively by desiring it more, living God’s will more fully, (equivalent to opening the door to allow grace to flow in - wider the doors open, the more can flow in.) We block it through deliberate sin, failure to cooperate and use the grace already given. (equivalent to opening the door only a little, or piling rocks in front of the opening.) Deliberate mortal sin is like closing the door. Sincere confession opens it again.
Nita