Psalm 139 is a powerful and intimate reflection on God's omniscience or all-knowing, omnipresence or ever-present, and omnipotence meaning all-powerful. Written by King David, it expresses deep feeling of how fully God knows each person, their thoughts, actions, and even words before they are spoken. He acknowledges God's thoughts as vast and precious, beyond human understanding. David invites God to search his heart, test his thoughts, and lead him in the way of righteousness.