War is the natural consequence of sin being in the world, and men and nations coveting the possessions of others. (James 4:1-3.) The principal wars recorded in Scripture are, however, different; they are those of Israel in taking possession of Canaan for Jehovah as the Lord's host, and in maintaining their position in His land, for which they had divine instruction. Their warfare is typical of the conflict of Christians against principalities, powers, and the rulers of the darkness of this world and against spiritual wickedness in the heavenlies. (Eph. 6:12.) There are also the wars against Israel, when God used other nations to punish them. But God always maintained His rights in His own people and in His own land.
When Jehovah destroyed the army of Pharaoh in the Red Sea, He was called "a man of war," and this and other victories were recorded in "the book of the wars of Jehovah." (Ex. 15:3: Num. 21:14.) David could say of God. "He teacheth my hands to war." 2 Sam. 22:35; Psa. 18:34.
There are still wars on the earth, for sin is here, and nation rises against nation, and when Israel is again in the land, they will be persecuted by their enemies. The kings of the habitable world will be gathered at Armageddon to the battle of that great day of God the Almighty. (Rev. 16:14, 16.) The Lord must reign until He hath put all enemies under His feet. This will be followed by a time when they "shall learn war no more." when warlike weapons will be beaten into agricultural instruments, and the Prince of Peace will reign over the whole earth.