Deuteronomy 26:16

16 On this day the Lord thy God charged thee to keep all the ordinances and judgments; and ye shall observe and do them, with all your heart, and with all your soul.

Deuteronomy 26:16 Meaning and Commentary

Deuteronomy 26:16

This day the Lord thy God hath commanded thee to do these
statutes and judgments
These are the words of Moses, as Aben Ezra rightly observes, and refer not only to the laws last mentioned, but to all others which he had repeated, or the Lord by him had ordered to be observed, recorded in this book: and though it is very probable Moses had been several days repeating former laws, and acquainting them with new ones; yet this being the last day, in which the whole account was finished, they are said to be commanded that day, and though commanded that day were to be observed and done every day; for, as Jarchi says, every day was to be considered and reckoned as new, as if on that day they were commanded them:

thou shall therefore keep and do them with all thy heart, and with all
thy soul;
cordially, readily, willingly, sincerely, constantly, and to the utmost of their abilities.

Deuteronomy 26:16 In-Context

14 And in my distress I did not eat of them, I have not gathered of them for an unclean purpose, I have not given of them to the dead; I have hearkened to the voice of the Lord our God, I have done as thou hast commanded me.
15 Look down from thy holy house, from heaven, and bless thy people Israel, and the land which thou hast given them, as thou didst swear to our fathers, to give to us a land flowing with milk and honey.
16 On this day the Lord thy God charged thee to keep all the ordinances and judgments; and ye shall observe and do them, with all your heart, and with all your soul.
17 Thou hast chosen God this day to be thy God, and to walk in all his ways, and to observe his ordinances and judgments, and to hearken to his voice.
18 And the Lord has chosen thee this day that thou shouldest be to him a peculiar people, as he said, to keep his commands;

The Brenton translation of the Septuagint is in the public domain.