How about posting the Ten Commandments in churches?

The answer is not outward—to post a physical copy to read, observe, or notice externally—no matter the location. We are to post them on our heart—not stone, paper, or cardboard:    “Let not steadfast love and faithfulness forsake you; bind them around your neck; write them on the tablet of your heart (Proverbs 3:3).” Only the Lord Christ can do this, as we are renewed by the Gospel and the Holy Spirit dwells within believers—apart from any inherent power in the Law or our ability to follow rules. “For this is the covenant that I will make with the house of Israel after those days, declares the Lord: I will put my law within them, and I will write it on their hearts. And I will be their God, and they shall be my people (Jer. 31:33).
—ed.