Moses
Deuteronomy 6:3ESV·traditional attribution

Hear therefore, O Israel, and be careful to do them, that it may go well with you, and that you may multiply greatly, as the LORD, the God of your fathers, has promised you, in a land flowing with milk and honey.

Matthew Henry Presbyterian @wholebiblehenry

Observe here, 1. That Moses taught the people all that, and that only, which God commanded him to teach them, Deu 6:1. Thus Christ's ministers are to teach his churches all that he has commanded, and neither more nor less, Mat 28:20. 2.

Commenting on Deuteronomy 6:1-3

John Gill Reformed Baptist @doctorgill

Hear therefore, O Israel, and observe to do it,.... Or them, the commandments given them: that it may be well with thee; in body and estate: and that ye may increase mightily; not only in wealth and riches, but chiefly in numbers: as the Lord God of thy fathers hath promised thee; a promise of increase of numbers was frequently made to Abraham, Isaac, and...

Geneva Bible Notes Reformed @genevanotes

Hear therefore, O Israel, and observe to do [it]; that it may be well with thee, and that ye may increase mightily, as the LORD God of thy fathers hath promised thee, in the land that floweth with milk and honey. (b) Which has an abundance of all things needed for man's life.