Commentaries
3:7-13 The waters of Jordan shall be cut off. This must be done in such a way as never was done, but in the dividing of the Red sea. That miracle is here repeated; God has the same power to finish the salvation of his people, as to begin it; the WORD of the Lord was as truly with Joshua as with Moses. God's appearances for his people ought to encourage faith and hope. God's work is perfect, he will keep his people. Jordan's flood cannot keep out Israel, Canaan's force cannot turn them out again.
Jos 3:7, 8. The Lord Encourages Joshua.
7, 8. the Lord said to Joshua, This day will I … magnify thee in the sight of all Israel—Joshua had already received distinguished honors (Ex 24:13; De 31:7). But a higher token of the divine favor was now to be publicly bestowed on him, and evidence given in the same unmistakable manner that his mission and authority were from God as was that of Moses (Ex 14:31).