David's heart is still upon praising God; and therefore, 1. He prays that God would give him time to praise him: "Let my soul live, and it shall praise thee, that is, let my life be prolonged, that I may live to thy glory." The reason why a good man desires to live is that he may praise God in the land of the living, and do something to his honour. Not, "Let me live and serve my country, live and provide for my family;" but, "Let me live that, in doing this, I may praise God here in this world of conflict and opposition." When we die we hope to go to a better world to praise him, and that is more agreeable for us, though here there is more need of us. And therefore one would not desire to live any longer than we may do God some service here. Let my soul live, that is, let me be sanctified and comforted, for sanctification and comfort are the life of the soul, and then it shall praise thee. Our souls must be employed in praising God, and we must pray for grace and peace that we may be fitted to praise God. 2. He prays that God would give him strength to praise him: "Let thy judgments help me; let all ordinances and all providences" (both are God's judgments) "further me in glorifying God; let them be the matter of my praise and let them help to fit me for that work."