The first words, "I will love thee, O Lord, my strength," are the scope and contents of the psalm. Those that truly love God, may triumph in him as their Rock and Refuge, and may with confidence call upon him. It is good for us to observe all the circumstances of a mercy which magnify the power of God and his goodness to us in it. David was a praying man, and God was found a prayer-hearing God. If we pray as he did, we shall speed as he did. God's manifestation of his presence is very fully described, Hebrews 5:7. God made the earth to shake and tremble, and the rocks to cleave, and brought him out, in his resurrection, because he delighted in him and in his undertaking.