Deuteronomy 1.41-43 Then you said to me, We have sinned against the Lord. We will go up and fight, as the Lord our God commanded us. And you girded on every man his battle weapons, and thought it a simple matter to go up into the hill country. And the Lord said to me, Say to them, Do not go up or fight, for I am not among you—lest you be dangerously hurt by your enemies. So I spoke to you, and you would not hear, but rebelled against the commandment of the Lord, and were presumptuous and went up into the hill country. (Amplified )

God had told the nation of Israel to go into the land of Canaan, and possess it. When the 12 spies (except for Caleb and Joshua) returned with a evil report of unbelief and doubt about taking the land due to the rough terrain and giants, God told them that their children, but not them, would enter the Promised Land. Convicted of their sin and unbelief, these same people told Moses that they were sorry, and we’re now ready to go up and fight the giants. But God told Moses to tell them that He would not be with them if they went up to fight against these people.

Two things are revealed here. One, the God-appointed time or opportunity to fight the battle was over. Two, to proceed in the battle when God commanded them not to was called presumptuous. The moral of the story is this. Timing is very important in obeying the commands of God. Some God given opportunities can never be recovered. Secondly, it is presumptuous to think that all of God’s commands and opportunities are “open ended”. To proceed in an endeavor when God forbids it is high handed sin, or presumption. This is dangerous. May The Lord help us to understand these lessons of life in Christ.