Psalms 18:2

The LORD [is] my rock, and my fortress, and my deliverer; my God, my strength, in whom I will trust; my buckler, and the horn of my salvation, [and] my high tower.

Ver. 2. The Lord is my rock, and my fortress, &c.] i.e. He is all in all for my preservation. Ten words, say the Hebrews, he here heapeth up, in reference to ten signal victories; or rather because his thankful heart was so enlarged, that he could never satisfy himself in saying what God had been to him and done for him; and hence this congeries, or heap of holy expressions; and all to show that God is a rock of refuge, a firm fortress, a receptacle of rest, a sanctuary of safety to all his saints in time of trouble. David had had his share, and had been put to his shifts; glad to hide himself, as he could, in rocks and strong holds that sheltered him from the storm. To these he alludeth when he calls God his rock, fortress, &c.

And my deliverer] Rocks and strong holds do not always deliver (witness the Shechemites, Jebusites, Arimasphes), but God always doth.

And the horn of my salvation] Qui veluti cornu petit et conficit hostes meos, saith Vatablus; who goreth and dispatcheth mine enemies. A metaphor either from horned beasts, or else (as some will have it) from the ancient custom of wearing horns of iron upon their helmet, for a crest or military ornament; whereupon the raised horn was a sign of victory, and the horn beaten down a sign of being overcome.