4 For your loving kindness is great above the heavens. Your faithfulness reaches to the skies.
*Minor differences ignored. Grouped by changes, with first version listed as example.
For thy mercy - This is taken from Psalm 57:10. The only change is in the expression "above the heavens," instead of "unto the heavens." The sense is essentially the same. The particular idea here, if it differs at all from the expression in Psalm 57:1-11, is, that the mercy of God seems to "descend" from heaven upon man, or "comes down" from on high.
For thy mercy is great above the heavens,..... It is in Psalm 57:10, "thy mercy is great unto the heavens". See Gill on Psalm 57:10.
*More commentary available at chapter level.