He trains my hands for battle;
my arms can bend a bow of bronze.
You make your saving help my shield,
and your right hand sustains me;
your help has made me great.
You provide a broad path for my feet,
so that my ankles do not give way. Psalm 18:34-36

David seems to be taking an inventory of his skills. These are the skills that the Lord himself has helped David with. He knows that he didn’t earn any of his skills but was endowed with them. He was strong because the Lord trained him. He was protected because God has been his shield. And he had sure footing because the Lord gave it to him.

Yes, David still had to work out to build up his strength, learn how to protect himself in hand-to-hand combat, and practice maneuvers that would keep him agile and mobile, but that’s not the point.

Ultimately King David knew where his strength lay: in God Almighty. He couldn’t rely on his strength, defense, or agility in the same way we might try to rely on ours. We know very well whet happens when we rely on our own abilities. But when they are turned over to the Lord for his purposes, we can certainly have the confidence that King David had when he wrote these verses.