Key verse: Exodus 20:18-19
All the people witnessed the thunder and lightning, the sound of the trumpet, and the mountain surrounded by smoke. When the people saw it they trembled and stood at a distance. “You speak to us, and we will listen,” they said to Moses, “but don’t let God speak to us, or we will die.” (CSB)

Notice…that, at least in this passage, the Ten Commandments are not called “commandments,” but rather “words.” Additionally, how to divide these words/commandments into ten isn’t necessarily as clear-cut as we might like it to be. Some Christian traditions see verse 2 as Preamble, whereas others see it as part of the first word/commandment. Some view verse 3 as constituting its own word/commandment, and some view it as part of the same thought as vv. 4-6. And some see verse 17 as one word/commandment, while others see it as two.
Regardless of how they’re divided, there’s a clear distinction between the first 3-4 and last 6-7 words/commandments. The first table relates to the people’s relationship with and worship of God, specifically. The second table relates to the people’s dealings with one another.

From the Apologetics Study Bible note on vv. 1-17, “God and Moses perceived obedience to the laws, not as a way of or precondition to salvation but as the grateful response of those who had already been saved. God did not reveal the law to the Israelites in Egypt and then tell them that as soon as they had measured up to this standard, he would rescue them. On the contrary, by grace alone, through faith they crossed the Red Sea to freedom.
The Decalogue begins not with the first commandment but with a preamble: “I am the LORD your God, who brought you out of the land of Egypt, out of the place of slavery” (v. 2; Dt 5:6). Obedience to the Decalogue or any other law has never been intended as the way of salvation but as the appropriate response to salvation already received.”

Answer: Which commandment does the LORD tell Moses to reiterate to the people in vv. 22-23? Do you suppose this reiteration is foreshadowing something?