More from Oswald Bayer:
Luther never downplays or treats as harmless the situation of temptation and testing when God withdraws and conceals himself. He confronts it in all its depth and sharpness. He does not ignore experiences of suffering. Yet he still refuses to accept their finality. He flees from the hidden God to the revealed and incarnate God.
Living by Faith , Chapter 6
The distinction between the “hidden God” and “the revealed God” is an important one. The hiddenness of God refers not only to times when God seems far away, as here, but also when God is active in the world without being perceived (as in, for example, vocation). It can also refer to the abstract God of the philosophers and to the God disclosed in the Law, full of wrath and judgment. Luther also speaks of God hidden in the Sacraments–truly present, though unseen–knowable only by His disclosure in His Word, apprehended by faith, so that He become the revealed God.