Psalm 43:2 (ESV)

2 For you are the God in whom I take refuge; why have you rejected me? Why do I go about mourning because of the oppression of the enemy?

There is tension in this verse. On the one hand, the poet confesses that God is his refuge. He knows he is safe with his God (see Psalm 27:1, Psalm 27:5). But on the other hand, he feels that God rejects him. The language here is sharper than forgotten (in Psalm 42:9). He feels cast away by God. He does not understand this. Why does it seem like God is letting him fall? This is really a painful mystery for him.