Matthew Henry Presbyterian @wholebiblehenry

Here is the repetition of the ten commandments, in which observe, 1. Though they had been spoken before, and written, yet they are again rehearsed; for precept must be upon precept, and line upon line, and all little enough to keep the word of God in our minds and to preserve and renew the impressions of it. We have need to have the same things often inculcated upon us.

Commenting on Deuteronomy 5:6-22

John Gill Reformed Baptist @doctorgill

And remember that thou wast a servant in the land of Egypt,.... Even a bondservant; for Egypt was an house of bondage, and there the Israelites were made to serve in hard bondage; of which they are reminded, that their hearts might be touched with it, and inclined to show pity to persons in somewhat similar circumstances; calling to mind how sweet a little rest...

Jamieson-Fausset-Brown Reformed @jfbcommentary

Keep the sabbath day to sanctify it, as the Lord thy God hath commanded thee--that is, keep it in mind as a sacred institution of former enactment and perpetual obligation. [See on Exo 20:8].