Two points for you to consider. First of all, I believe God prefaces His instructions with a reference to His demonstrated actions as a way of establishing His bona fides for being able to command the Israelites to do something. It’s not to different than a mother saying “I’m your mother who looks after you and who has cared for you all these years so you better do what I say”. It isn’t so much that God is saying to the Israelites, “You must do these things that I command because I already did something for you” as it is God saying, “I’m God, and the proof is in what you have seen me do. Now I want you to follow these Laws so you may live before me and prosper. If you don’t follow these Laws, then you will die.”
The second point is that Scripture supports you claim about actions affecting the disposition of the heart:
- Proverbs 22:6 Train up a child in the way he should go, Even when he is old he will not depart from it.
- Proverbs 22:15 Foolishness is bound up in the heart of a child; The rod of discipline will remove it far from him.
- Proverbs 15:32 He who neglects discipline despises himself, But he who listens to reproof acquires understanding.
- Hebrews 12:7–11 It is for discipline that you endure; God deals with you as with sons; for what son is there whom his father does not discipline? But if you are without discipline, of which all have become partakers, then you are illegitimate children and not sons. Furthermore, we had earthly fathers to discipline us, and we respected them; shall we not much rather be subject to the Father of spirits, and live? For they disciplined us for a short time as seemed best to them, but He disciplines us for our good, so that we may share His holiness. All discipline for the moment seems not to be joyful, but sorrowful; yet to those who have been trained by it, afterwards it yields the peaceful fruit of righteousness.