Rock. — Better here, cliff, keeping “rock” for the next clause. In the first figure the ideas of height and shelter, in the second of broad-based and enduring strength, are predominant.
Fortress. — Properly, mountain castle. We have the joint figure of the lofty and precipitous cliff with the castle on its crest, a reminiscence — as, in fact, is every one in this “towering of epithets” — of scenes and events in David’s early life.
My God... — Better, my God, my rock, I trust in Him. God is here El, “the strong one.” In Samuel, “God of my rock.”
Horn of my salvation. — The allusion seems to be not to a means of attack, like the horn of an animal, but to a mountain peak (called “horn” in all languages — so κέρας, Xen. Anab. v. 6; “Cornua Parnassi,” Statius, Theb. v. 532; and so in Hebrew, Isaiah 5:1, see margin), such as often afforded David a safe retreat. Render “my peak of safety.”
High tower. — The LXX. and Vulgate have “helper.” (Comp. Psalms 9:9.) The word comes in so abruptly, that doubtless the addition in Samuel, “and my refuge, my Saviour, thou savest me from violence,” was part of the original hymn, completing the rhythm.