From The Treasury of David, by Martin LutherHave mercy on me, O God, according to your steadfast love; according to your abundant mercy blot out my transgressions. Ps. 51:1 David is talking to the God of his fathers the God who promised. The people of Israel did not have a God who was viewed as absolutely. Human weakness cannot help being crushed by the majesty of the absolute God, as Scripture reminds us over and over. Let no one, therefore, interpret David as speaking with the absolute God. He is speaking with God as he is dressed and clothed in his word and promises, whom God promised to Adam and the other patriarchs. We must take hold of this God, not naked but clothed and revealed in his word. Otherwise certain despair will crush us. This distinction must always be made between the Prophets who speak with God and the pagans. Pagans speak with God outside his word and promises, according to the thoughts of their own hearts. But the Prophets speak with God as he is clothed and revealed in his promises and word. This God, clothed in kind appearance and dressed in his promises this God we can grasp and look at with joy and with trust. The absolute God, on the other hand, is like an iron wall against which we cannot bump without destroying ourselves. Therefore Satan is busy day and night, making us run to the naked God so that we forget his promises and blessings shown in Christ, and think about God and the judgment of God. But David speaks with the God of his fathers, with the God whose promises he knows and whose mercy and grace he has felt. He could depend on Gods promises as he prayed because the promises include Christ.