Charles H. Spurgeon on Psalms 18:34

"He teacheth my hands to war." Martial prowess and skill in the use of weapons are gratefully acknowledged to be the result of divine teaching; no sacrifice is offered at the shrine of self in praise of natural dexterity, or acquired skilfulness; but, regarding all warlike prowess as a gift of heavenly favour, thankfulness is presented to the Giver. The Holy Spirit is the great Drillmaster of heavenly soldiers. "So that a bow of steel is broken by mine arms." A bow of brass is probably meant, and these bows could scarcely be bent by the arms alone, the archer had to gain the assistance of his foot; it was, therefore, a great feat of strength to bend the bow, so far as even to snap it in halves. This was meant of the enemies' bow, which he not only snatched from his grasp, but rendered useless by breaking it in pieces. Jesus not only destroyed the fiery suggestions of Satan, but he broke his arguments with which he shot them, by using Holy Scripture against him; by the same means we may win a like triumph, breaking the bow and cutting the spear in sunder by the sharp edge of revealed truth. Probably David had by nature a vigorous bodily frame; but it is even more likely that, like Samson, he was at times clothed with more than common strength; at any rate, he ascribes the honour of his feats entirely to his God. Let us never wickedly rob the Lord of his due, but faithfully give unto him the glory which is due unto his name.