Thy mercy, O Lord, is in the heavens. Instead of the usual contrast between the wicked man and the godly one (Psalms 1:1-6; Psalms 4:2, Psalms 4:3; Psalms 5:10, Psalms 5:11, etc.), the psalmist here makes the startling contrast between the wicked man and God!
The character of the wicked man is given in four verses (Psalms 36:1-4), the portrait of God in five (Psalms 36:5-9). God's first and principal characteristic is "mercy"—or rather, "loving-kindness" ( חסר).
This quality is revealed, not on earth only, but also in heaven, towards the angels. Thy faithfulness reacheth unto the clouds. Next to loving-kindness in God comes "faithfulness"—fidelity to every promise that he has ever made, unswerving attachment to those whom he has once loved, undeviating maintenance of the truth (comp.