He teacheth my hands to war
From whence it appears, that war, in some cases, is lawful; and that all the skilfulness and art in training men for war, in the use of armour, in marshalling of armies, in forming sieges is all from God; see ( Psalms 144:1 ) ; and so is all that spiritual skill, in making use of the whole armour of God against every enemy, sin, Satan, and the world; and even the wisdom and skill, counsel and instruction, which Christ as man and Mediator had, when it was the hour and power of darkness; when he was engaged with principalities and powers, and got the victory over them, were from the Lord: see ( Psalms 16:7 ) ;
so that a bow of steel is broken by mine arms;
that is, the bow of an enemy falling into his hands, which might be literally true of David. It is in the Hebrew text, "a bow of brass"; and so Apollinarius renders it; which Kimchi and Ben Melech interpret strong iron, that is, steel; and so the Targum; see ( Job 20:24 ) ; Satan is an archer; his temptations are darts, and fiery ones; and his strong bow may be said to be broken by the arms of faith, when his temptations, under the influence of divine grace, are repelled and rendered ineffectual; and especially his bow was broken by Christ, not only in the wilderness, when he was vanquished by him; but in the garden, and on the cross, when Satan could find nothing in him, and get no other advantage over him, but to bruise his heel; when he himself had his head broke, his works ruined, and he himself destroyed. Some render the words, "mine arms have bent a bow of steel": that is, such skill and strength were given him that he was able to bend, draw, and shoot a bow or steel: the Targum is, "and hath strengthened mine arm as a bow of brass", or "steel"; and so the Syriac and Arabic versions; and to the same purpose the Septuagint, Vulgate Latin, and Ethiopic versions; or it may be rendered, "my arms have bent", or "made to descend F15, a bow of brass"; for when a bow is bent, the horns or corners of it are made to descend towards a man.