41 And now, Israel, hearken to the statutes and to the ordinances which I teach you, to do [them], that ye may live, and go in and possess the land which Jehovah the God of your fathers giveth you. 2 Ye shall not add to the word which I command you, neither shall ye take from it, that ye may keep the commandments of Jehovah your God which I command you. 3 Your eyes have seen what Jehovah did because of Baal-Peor; for all the men that followed Baal-Peor, Jehovah thy God hath destroyed them from among you; 4 but ye that did cleave to Jehovah your God are alive every one of you this day. 5 See, I have taught you statutes and ordinances, even as Jehovah my God commanded me, that ye may do so in the land into which ye enter to possess it. 6 And ye shall keep and do them; for that will be your wisdom and your understanding before the eyes of the peoples that shall hear all these statutes, and say, Verily this great nation is a wise and understanding people. 7 For what great nation is there that hath God near to them as Jehovah our God is in everything we call upon him for? 8 And what great nation is there that hath righteous statutes and ordinances, as all this law which I set before you this day?
9 Only take heed to thyself, and keep thy soul diligently, lest thou forget the things that thine eyes have seen (and lest they depart from thy heart all the days of thy life; but thou shalt make them known to thy sons and to thy sons' sons),
Matthew Henry's Commentary on Deuteronomy 4:1-9
Commentary on Deuteronomy 4:1-23
(Read Deuteronomy 4:1-23)
The power and love of God to Israel are here made the ground and reason of a number of cautions and serious warnings; and although there is much reference to their national covenant, yet all may be applied to those who live under the gospel. What are laws made for but to be observed and obeyed? Our obedience as individuals cannot merit salvation; but it is the only evidence that we are partakers of the gift of God, which is eternal life through Jesus Christ, Considering how many temptations we are compassed with, and what corrupt desires we have in our bosoms, we have great need to keep our hearts with all diligence. Those cannot walk aright, who walk carelessly. Moses charges particularly to take heed of the sin of idolatry. He shows how weak the temptation would be to those who thought aright; for these pretended gods, the sun, moon, and stars, were only blessings which the Lord their God had imparted to all nations. It is absurd to worship them; shall we serve those that were made to serve us? Take heed lest ye forget the covenant of the Lord your God. We must take heed lest at any time we forget our religion. Care, caution, and watchfulness, are helps against a bad memory.