To the Lord our God belong mercies and forgivenesses - Not only does righteousness belong to him in the sense that he has done right, and that he cannot be blamed for what he has done, but mercy and forgiveness belong to him in the sense that he only can pardon, and that these are attributes of his nature.
Though we have rebelled against him - The word used here and rendered “though” (כי kı̂y) may mean either “though” or “for.” That is, the passage may mean that mercy belongs to God, and we may hope that he will show it, “although” we have been so evil and rebellious; or it may mean that it belongs to him, and he only can show it, “for” we have rebelled against him; that is, our only hope now is in his mercy, “for” we have sinned, and forfeited all claims to his favor. Either of these interpretations makes good sense, but the latter would seem to be most in accordance with the general strain of this part of the prayer, which is to make humble and penitent confession. So the Latin Vulgate “quia.” So Theodotion, ὅτι hoti. So Luther and Lengerke, “denn.” In the same way, the passage in Psalms 25:11 is rendered, “For thy name’s sake, O Lord, pardon mine iniquity, for (כי kı̂y) it is great” - though this passage will admit of the other interpretation, “although it is great.”