Contradiction with Hebrews 10:16
While Proverbs 7:3 emphasizes writing commandments upon the heart, Hebrews 10:16 speaks of God writing his laws directly on hearts and minds, suggesting a divine rather than human effort.
Hebrews 10:16: This [is] the covenant that I will make with them after those days, saith the Lord, I will put my laws into their hearts, and in their minds will I write them;
Contradiction with 2 Corinthians 3:3
Proverbs 7:3 suggests an individual effort in writing words upon one's heart, whereas 2 Corinthians 3:3 explains that believers are an epistle of Christ written by the Spirit, indicating a divine initiative.
2 Corinthians 3:3: [Forasmuch as ye are] manifestly declared to be the epistle of Christ ministered by us, written not with ink, but with the Spirit of the living God; not in tables of stone, but in fleshy tables of the heart.
Contradiction with Jeremiah 31:33
Proverbs argues for individual action to inscribe commandments; Jeremiah instead points to God's action in writing the law on hearts.
Jeremiah 31:33: But this [shall be] the covenant that I will make with the house of Israel; After those days, saith the LORD, I will put my law in their inward parts, and write it in their hearts; and will be their God, and they shall be my people.