David opens Psalm 37 with a plain command: do not fret because of evildoers and do not envy them, for they will wither like the grass. The lesson sets this beside Asaph’s confession in Psalm 73, where the prosperity of the wicked nearly made him stumble until he entered the sanctuary of God and saw their end. The luxurious life of the evildoer is real, but it is short, and the days of the wicked are numbered.
Over against this stands the Lord who watches over His people, whose eye is on those who fear Him. The response of the godly is to trust in the Lord and do good, to delight in Him, to commit their way to Him, and to rest and wait patiently. The one who delights in the Lord finds his desires shaped by God’s good will, and learns that a little with the righteous is better than the abundance of many wicked.