Reading through the Bible together
For the most part, the people who had made the original covenant at Sinai had died in the wilderness. The generation of unbelief had died, now it was an opportunity for the generation of faith to arise. So, Moses is basically renewing the covenant with the new group of people.
Israel saw great wonders from the hand of God since coming from Egypt. The older ones were but children then, and they saw the plagues; they saw the death of the firstborn; they saw the Red Sea parted, and they saw the Egyptian armies destroyed. And all of them saw victories won by prayer in the wilderness; they ate the manna; they drank the miraculously provided water; and they saw miracle after miracle.
God will never override our choices to yield to our perverse self-oriented ways. The miracles, in and of themselves, could not accomplish anything in the hearts of Israel. If God did not send His Spirit to change their hearts and if they did not yield, then the greatest wonders imaginable would not make a difference.
Some people today think the greatest help for 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 God's supernatural work in someone’s heart and their corresponding willingness to be taught.
Chinese Union Mission