3 and shall say unto them, Hear, O Israel, ye draw nigh this day unto battle against your enemies: let not your heart faint; fear not, nor tremble, neither be ye affrighted at them; 4 for Jehovah your God is he that goeth with you, to fight for you against your enemies, to save you.
Matthew Henry's Commentary on Deuteronomy 20:3-4
Commentary on Deuteronomy 20:1-9
(Read Deuteronomy 20:1-9)
In the wars wherein Israel engaged according to the will of God, they might expect the Divine assistance. The Lord was to be their only confidence. In these respects they were types of the Christian's warfare. Those unwilling to fight, must be sent away. The unwillingness might arise from a man's outward condition. God would not be served by men forced against their will. Thy people shall be willing, Isaiah 8:12.