Charles H. Spurgeon on Psalms 59:17

Unto thee, O my strength, will I sing. What transport is here! What a monopolising of all his emotions for the one object of praising God! Strength has been overcome by strength; not by the hero's own prowess, but by the might of God alone. See how the singer girds himself with the almightiness of God, and calls it all his own by faith. Sweet is the music of experience, but it is all for God; there is not even a stray note for man, for self, or for human helpers. For God is my defence, and the God of my mercy. With full assurance he claims possession of the Infinite as his protection and security. He sees God in all, and all his own. Mercy rises before him, undisturbed and manifold, for he feels he is undeserving, and security is with him, undisturbed and impregnable, for he knows that he is safe in divine keeping. Oh, choice song! My soul would sing it now in defiance of all the dogs of hell. Away, away, ye adversaries of my soul, the God of my mercy will keep ye all at bay —

"Nor shall the infernal lion rend

Whom he designs to keep."