Because God has made thee as the stars of heaven for multitude (so the preceding chapter concludes), therefore thou shalt love the Lord thy God (so this begins). Those whom God has built up into families, whose beginning was small, but whose latter end greatly increases, should use that as an argument with themselves why they should serve God. Thou shalt keep his charge, that is, the oracles of his word and ordinances of his worship, with which they were entrusted and for which they were accountable. It is a phrase often used concerning the office of the priests and Levites, for all Israel was a kingdom of priests, a holy nation. Observe the connection of these two: Thou shalt love the Lord and keep his charge, since love will work in obedience, and that only is acceptable obedience which flows from a principle of love. Jo1 5:3.
Mention is made of the great and terrible works of God which their eyes had seen, Deu 11:7. This part of his discourse Moses addresses to the seniors among the people, the elders in age; and probably the elders in office were so, and were now his immediate auditors: there were some among them that could remember their deliverance out of Egypt, all above fifty, and to them he speaks this, not to the children, who knew it by hearsay only, Deu 11:2. Note, God's mercies to us when we were young we should remember and retain the impressions of when we are old; what our eyes have seen, especially in our early days, has affected us, and should be improved by us long after. They had seen what terrible judgments God had executed upon the enemies of Israel's peace, 1. Upon Pharaoh and the Egyptians that enslaved them. What a fine country was ruined and laid waste by one plague after another, to force Israel's enlargement! Deu 11:3. What a fine army was entirely drowned in the Red Sea, to prevent Israel's being re-enslaved! Deu 11:4. Thus did he give Egypt for their ransom, Isa 43:3. Rather shall that famous kingdom be destroyed than that Israel shall not be delivered. 2. Upon Dathan and Abiram that embroiled them. Remember what he did in the wilderness (Deu 11:5), by how many necessary chastisements (as they are called, Deu 11:2) they were kept from ruining themselves, particularly when those daring Reubenites defied the authority of Moses and headed a dangerous rebellion against God himself, which threatened the ruin of a whole nation, and might have ended in that if the divine power had not immediately crushed the rebellion by burying the rebels alive, them and all that was in their possession, Deu 11:6. What was done against them, though misinterpreted by the disaffected party (Num 16:41), was really done in mercy to Israel. To be saved from the mischiefs of insurrections at home is as great a kindness to a people, and therefore lays them under as strong obligations, as protection from the invasion of enemies abroad.

But your eyes have seen all the great acts of the Lord which he did; Even all before related, with many others; and therefore the instruction they should learn from thence should be as follows.
But your eyes have seen all the great acts of the Lord which he did; Even all before related, with many others; and therefore the instruction they should learn from thence should be as follows.
Deuteronomy 11:8

deu 11:8
deu 11:8
deu 11:8Therefore shall you keep all the commandments which I command you this day,.... For the reasons before suggested, as well as for what follow:

that ye may be strong; healthful in body, and courageous in mind, for sin tends to weaken both; whereas observance of the commands of God contributes to the health and strength of the body, and the rigour of the mind; both which were necessary to the present expedition they were going upon:

and go in and possess the land whither ye go to possess it; the land of Canaan, they were marching towards in order to possess it; and nothing would more inspire them with courage, and cause them to enter it manfully without fear of their enemies, than obedience to the commands of God; whose presence being promised them on that account, they might expect it, and so had nothing to fear from the inhabitants of the land.

I speak not with your children which have not known . . . But your eyes have seen all the great acts of the Lord which he did--Moses is here giving a brief summary of the marvels and miracles of awful judgment which God had wrought in effecting their release from the tyranny of Pharaoh, as well as those which had taken place in the wilderness. He knew that he might dwell upon these, for he was addressing many who had been witnesses of those appalling incidents. For it will be remembered that the divine threatening that they should die in the wilderness, and its execution, extended only to males from twenty years and upward, who were able to go forth to war. No males under twenty years of age, no females, and none of the tribe of Levi, were objects of the denunciation (see Num 14:28-30; Num 16:49). There might, therefore, have been many thousands of the Israelites at that time of whom Moses could say, "Your eyes have seen all the great acts which He did"; and with regard to those the historic review of Moses was well calculated to stir up their minds to the duty and advantages of obedience.