Deu 29:1-9 These are the words of the covenant that the LORD commanded Moses to make with the people of Israel in the land of Moab, besides the covenant that he had made with them at Horeb. And Moses summoned all Israel and said to them: “You have seen all that the LORD did before your eyes in the land of Egypt, to Pharaoh and to all his servants and to all his land, the great trials that your eyes saw, the signs, and those great wonders. But to this day the LORD has not given you a heart to understand or eyes to see or ears to hear. I have led you forty years in the wilderness. Your clothes have not worn out on you, and your sandals have not worn off your feet. You have not eaten bread, and you have not drunk wine or strong drink, that you may know that I am the LORD your God. And when you came to this place, Sihon the king of Heshbon and Og the king of Bashan came out against us to battle, but we defeated them. We took their land and gave it for an inheritance to the Reubenites, the Gadites, and the half-tribe of the Manassites. Therefore keep the words of this covenant and do them, that you may prosper in all that you do.
This was not a new covenant in addition to that made at Sinai, but simply a renewal and reaffirmation of that covenant. At Sinai the covenant was, properly speaking, made; sacrifices were then offered, and the people were sprinkled with the sacrificial blood, whereby the covenant was ratified, but on the occasion here referred to, no sacrifices were offered, for this was merely the recognition of the covenant formerly made as still subsisting.
Some 40 years before this, at Horeb (Mount Sinai), Israel made a covenant with God: Then he took the Book of the Covenant and read in the hearing of the people. And they said, “All that the LORD has said we will do, and be obedient.” And Moses took the blood, sprinkled it on the people, and said, “This is the blood of the covenant which the LORD has made with you according to all these words.” For the most part, the people who had the blood of the covenant sprinkled upon them had died in the wilderness. The generation of unbelief had died, now it was an opportunity for the generation of faith. So, Moses will reconfirm the covenant with the new generation.
Israel saw great wonders from the hand of God since coming from Egypt. They saw the plagues, they saw the death of the firstborn, they saw the Red Sea parted, they saw the Egyptian armies destroyed, they saw victories won by prayer, they ate the manna, they drank the miraculously provided water, and they saw miracle after miracle. Some people today think the greatest help to evangelism would be to see more miraculous events. After all, who could not believe in the face of such displays of spiritual power? But seeing great wonders accomplishes nothing apart from a supernatural work of God in someone’s heart.
During their forty years in the wilderness, their clothes did not wear out, their sandals did not wear out, and though they had no bread to eat or wine to drink, their needs were provided for. Israel conquered over their enemies, and they took their land.
Plainly, these are remarkable miracles. Clothes and sandals simply do not last 40 years of hard marching in the wilderness apart from a miracle. The wilderness does not provide enough food and water to meet the needs of some two million people apart from a miracle. A nation of slaves for 400 years does not conquer standing nations and take their land apart from a miracle. Seeing these great works of God, there is one logical response. Knowing the greatness of God’s love and power should make Israel more committed than ever to His covenant. (Guzik)
Both former mercies, and fresh mercies, should be thought on by us as motives to obedience. The hearing ear, and seeing eye, and the understanding heart, are the gift of God. All that have them, have them from him. God gives not only food and raiment, but wealth and large possessions, to many to whom he does not give grace. Many enjoy the gifts, who have not hearts to perceive the Giver, nor the true design and use of the gifts. We are bound, in gratitude and interest, as well as in duty and faithfulness, to keep the words of the covenant. (Henry)