The second principle of GOD on the topic of when,where and how to fight is to NOT rebel against GOD. It is written, " notwithstanding ye would not go up, but rebelled against The Commandment of THE LORD your GOD; and ye murmured in your tents, and said, 'because THE LORD hated us, HE hath brought us forth out of the land of Egypt, to deliver us into the hands of the Amorites, to destroy us. Whither shall we go up? our brethren have discouraged our heart, saying, 'the people is greater and taller than we; the cities are great, and walled up to heaven; and moreover we have seen the sons of An-a-kims there. ' Then said I unto you, 'dread not, neither be ye afraid of them. 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, and in the wilderness where thou hast seen how that THE LORD thy GOD bare thee, as a man doth bear his son, in all the way, that ye went, until ye came into this place'. " Deuteronomy 1:26-31

The third principle of GOD about warfare is NOT to fight if GOD is not in the battle with you. It is written," then ye answered and said unto me, 'we have sinned against THE LORD; we will go up and fight according to all that THE LORD our GOD commanded us.' And when ye had girded on every man his weapons of war, ye were ready to go up into the hill. And THE LORD said unto me, 'say unto them, go not up, neither fight; for I AM not among you; lest ye be smitten before your enemies.' So I spake unto you, and ye would not hear, but rebelled against the Commandment of THE LORD and went presumptously up into the hill. And the Amorites which dwelt in that mountain, came out against you, and chased you, as bees do, and destroyed you in Seir even unto Hormah. And ye returned and went before THE LORD, but THE LORD would not hearken to your voice, nor give ear unto you. " Deuteronomy 1:41-45

The fourth principle of GOD about warfare seems to be * that when you do battle GOD's way, you win. It is written, " And THE LORD said unto me, 'behold, I have begun to give Sihon and his land before thee; begin to possess that thou mayest inherit his land. Then Sihon came out against the us, he and all his people, to fight at Jahaz, and THE LORD our GOD delivered him before us, and we smote him, and his sons, and all his people." Deuteronomy 2: 31-22

The fifth principle of GOD about fighting a war, seems to be not to provoke GOD, and not to jump ahead of GOD. It is written, " And I  [Moses speaking] commanded Joshua at that time, saying 'thine eyes have seen all that THE LORD your GOD hath done unto these two kings; so shall THE LORD do unto all the kingdoms whither thou passest. Ye shall not fear them, for THE LORD your GOD HE shall fight for you.' And I besought THE LORD at that time saying, " O LORD GOD, THOU hast begun to shew THY servant THY greatness, and THY MIGHTY HAND; for what GOD is there in heaven and in earth, that can do according to THY works and according to THY might? I pray thee, let me go over, and see the good land that is beyond Jordan, that goodly mountain, and Lebanon. But THE LORD was wroth with me for your sakes, and would not hear me, and THE LORD said unto me, 'let it suffice thee, speak no more unto ME of this matter. "  Deuteronomy 3:21- 26

* I am basing the assigning of numbers upon where in The Bible the scripture is found and following the Bible chronology.