If his children forsake my law, and walk not in my judgments;
The writer of this psalm approaches God's throne with the covenant made to David as his anchor: God promised to sustain His favor toward this people forever through their king. He rehearses God's power in all creation and His faithfulness in redemption, yet the complaint that follows cuts sharp, God has seemingly abandoned His Church to her enemies, withdrawn all help and comfort, as though He had forgotten His own word.
AI summary
Commenting on Psalm 89:1-52
If his children forsake my law, and walk not in my judgments. It was possible, terribly possible, that David's posterity might wander from the Lord; indeed they did so, but what then? Was the mercy of God to pass away from David's seed?—far from it. So, too, the seed of the Son of David are apt to start aside, but are they therefore cast away?
The covenant God made with David and his seed was mentioned before (Psa 89:3, Psa 89:4); but in these verses it is enlarged upon, and pleaded with God, for favour to the royal family, now almost sunk and ruined; yet certainly it looks at Christ, and has its accomplishment in him much more than in David; nay, some passages here are scarcely applicable at all...
Commenting on Psalm 89:19-37