Deuteronomy 1-4…Israel refuses to enter the promised land, they wander in the wilderness for years, Moses is forbidden to enter the land, and God commands obedience through Moses.
Unbelief is at the core of all sin. In Deuteronomy 1, unbelieving hearts were driving the refusal to enter the land. All disobedience to God’s laws, and distrust of his power and goodness, flow from disbelief of his word, as all true obedience springs from faith.
Only a short account of the long stay of Israel in the wilderness is given in Deuteronomy 2. God not only rebuked them for their unbelief, but prepared them for Canaan by humbling them, teaching them to hate their lusts, to follow God, and to find contentment in Him.
God’s refusal to answer Moses’ prayer to enter the promised land is a helpful lesson for us. God matures us by denying many things we desire. He hears all our prayers, but doesn’t give us all we pray for. The prosperity gospel ignores Deuteronomy 3, because Moses’ lack of faith wasn’t the reason for him not getting what he wanted. God is good, and disciplines those He loves, which often includes holding back things we want.
We see even in Deuteronomy 4 that we cannot earn our salvation. Our obedience as individuals cannot merit a right relationship with God. but it is the only evidence that we are saved. We are saved by faith alone, through grace alone, but our faith should not be alone without fruit. A fruitless faith is described by Jesus in Matthew 13 (The Parable of the Sower) as being one that doesn’t result in eternal life.