That Ugly Beast and Enemy of God

...just as Abraham "believed God, and it was counted to him as righteousness"?
Galatians 3:6

Let your faith supplant reason. Abraham mastered reason by faith in the Word of God. Not as though reason ever yields meekly. It put up a fight against the faith of Abraham. Reason protested that it was absurd to think that Sarah who was ninety years old and barren by nature, should give birth to a son. But faith won the victory and routed reason, that ugly beast and enemy of God. Everyone who by faith slays reason, the world's biggest monster, renders God a real service, a better service than the religions of all races and all the drudgery of meritorious monks can render.
--Martin Luther, Commentary on the Epistle to the Galatians, p. 73