What does Psalm 56:13 mean?

David was so sure the Lord would rescue him from the Philistines and Saul that he wrote as if the rescue had already been accomplished. This technique is seen in several of David's psalms (Psalm 3:7–8; 9:5–6; 52:9).

In response to the Lord's protection, David would walk before God in "the light of life." Jesus referred to Himself as "the light of the world," and said, "Whoever follows me will not walk in darkness, but will have the light of life" (John 8:12). The Bible often uses "light" as a metaphor for truth, goodness, and virtue. David was grateful that God had delivered him from death, but God has delivered all who trust in His Son from spiritual death (Ephesians 2:1–5) and from eternal death (John 3:16). The apostle Paul writes in 2 Corinthians 4:6: "For God, who said, 'Let light shine out of darkness,' has shone in our hearts to give the light of the knowledge of the glory of God in the face of Jesus Christ."