Moses
Deuteronomy 5:2ESV·traditional attribution

The LORD our God made a covenant with us in Horeb.

John Calvin Reformed @genevareformer

2. The Lord our God. In these words he commends the Law; because it must be accounted a peculiar blessing, and a very high honor to be taken into covenant by God. Wherefore, that they may anxiously prepare themselves to embrace the Law, he says that what was above all things to be desired had been freely offered to them, viz., that they should be united in covenant with God.

Matthew Henry Presbyterian @wholebiblehenry

Here, 1. Moses summons the assembly. He called all Israel; not only the elders, but, it is likely, as many of the people as could come within hearing, Deu 5:1. The greatest of them were not above God's command, nor the meanest of them below his cognizance; but they were all bound to do. 2.

Commenting on Deuteronomy 5:1-5

John Gill Reformed Baptist @doctorgill

The Lord our God made a covenant with us in Horeb. Which is Sinai, as Aben Ezra observes; it being the same mountain, only it had two tops, which bore these different names; for certain it is that the decalogue after repeated was given at Sinai, and had the nature and form of a covenant; see Exo 24:7. .