“To the choirmaster. A Psalm of David, the servant of the Lord, who addressed the words of this song to the Lord on the day when the Lord delivered him from the hand of all his enemies, and from the hand of Saul. He said: I love you, O Lord, my strength.” -Psalm 18:title–1f
This psalm marks the point at which David’s power was at its height, likely before his great sin with Bathsheba left its shadow on him and his kingdom. It opens with a confession of his love for the Lord, the covenant savior from which he derives his strength. The word translated “love” here is, ironically, an uncommon word. It is, according to Derick Kidner, an emotional and impulsive word that is only used elsewhere in Scripture to express the love of the stronger for the weaker.
In this case, it is the weaker, expressing love spontaneously, for the stronger.