Before the Israelites crossed the Jordan into the Promised Land, Moses had much to say. One thing Moses highlighted was God’s power and presence with his people as they went. Here’s what Moses said in Deuteronomy 31:3-6:
As for the LORD your God, he is about to cross over before you; he will destroy these nations before you and dispossess them. As for Joshua, he is about to cross before you just as the LORD has said. The LORD will do to them just what he did to Sihon and Og, the Amorite kings, and to their land, which he destroyed. The LORD will deliver them over to you and you will do to them according to the whole commandment I have given you. Be strong and courageous! Do not fear or tremble before them, for the LORD your God is the one who is going with you. He will not fail you or abandon you!” (The NET Bible).
I appreciate Peter Craigie’s comments on these verses:
In his exhortation to the people, Moses returns once again to familiar themes from earlier portions of his address. Soon the people were to cross the Jordan and to begin the most critical phase of their conquest of the promised land. The people would not enter the battle alone: they would be preceded by the Lord (cf. 9:3) and their new leader, Joshua. The Israelites had already experienced God’s victory against Sihon and Og (cf. 2:26–37; 3:1–11) and thus they could advance in the certain knowledge, based on experience, of further victories through God’s strength.
They are urged to be strong and be courageous (v. 6); the strength and courage would come not from confidence in their own abilities, but from confidence in God, the one marching with you. The strength and courage of the warriors of God would lie in the disposition of their minds during the battle. Though they would be engaged physically in the fighting, their minds would not be focused on the enemy, whose threatening presence could easily undermine confidence, but rather their minds would be fixed on God, who would not fail or forsake them (v. 6b). With full confidence in the presence of God in their midst, the army of the Lord could not fail to be victorious in the conquest, and soon the land which had been promised so long ago would become their possession in reality.
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