Num 10:9
“If ye go to war in your land against the enemy who oppresses you, and ye blow the trumpets, ye shall bring yourselves to remembrance before Jehovah, and shall be saved (by Him) from your enemies.” מלחמה בּוא, to come into war, or go to war, is to be distinguished from למּלחמה בּוא, to make ready for war, go out to battle (Num 31:21; Num 32:6).