Matthew Poole and continuators on Deuteronomy 1:30

30 The LORD your God which goeth before you, he shall fight for you, according to all that he did for you in Egypt before your eyes;

Where you were weak, dispirited, divided, raw and unexperienced and in a great measure unarmed, and able to do nothing against your numerous potent, united Enemies, but to stand still and see the salvation of God. And therefore now your distrust is highly unreasonable, when you have been hardned and fitted for military service by your travels, disciplined and experienced in some degree as to Martial Affairs, encouraged by frequent and glorious Miracles for 40 years together, and you are going into a Country divided into several Nations and Kingdoms.