What does Psalm 55:16 mean?

Fear is natural when facing extreme danger. David was pursued by violent enemies (Psalm 55:2–5) and betrayed by a former ally (Psalm 55:12–13). Earlier in this psalm, David wished he could fly away from trouble to hide in the wilderness (Psalm 55:6–8). Yet he does not abandon belief in God. Instead, David expresses deep trust in the Lord. Though he is—or was—gripped by terror, David prays to God with confidence.

In calling upon God, David used the name "Lᴏʀᴅ," using the Hebrew term YHWH, God's covenant name. David depended upon the Lord to keep His promises about David's kingship and its perpetuity. The Lord promised in 2 Samuel 7:9, 11: "I have been with you wherever you went and have cut off all your enemies from before you. And I will make for you a great name, like the name of the great ones of the earth. … And I will give you rest from all your enemies. Moreover, the Lᴏʀᴅ declares to you that the Lᴏʀᴅ will make you [a dynasty]." David prayed with confidence because he was relying on the Lord's promises.