Augustine of Hippo
Catena Aurea · Lukasevangelium 11
And he said unto them, Which of you shall have a friend, and shall go unto him at midnight, and say unto him, Friend, lend me three loaves; For a friend of mine in his journey is come to me, and I have nothing to set before him? And he from within shall answer and say, Trouble me not: the door is now shut, and my children are with me in bed; I cannot rise and give thee. I say unto you, Though he will not rise and give him, because he is his friend, yet because of his importunity he will rise and give him as many as he needeth.
(de Quæst. Ev. lib. ii. qu. 21.) Or else, the friend to whom the visit is made at midnight, for the loan of the three loaves, is evidently meant for an allegory, just as a person set in the midst of trouble might ask God that He would give him to understand the Trinity, by which he may console the troubles of this present life. For his distress is the midnight in which he is compelled to be so urgent in his request for the three. Now by the three loaves it is signified, that the Trinity is of one substance. But the friend coming from his journey is understood the desire of man, which ought to obey reason, but was obedient to the custom of the world, which he calls the way, from all things passing along it. Now when man is converted to God, that desire also is reclaimed from custom. But if not consoled by that inward joy arising from the spiritual doctrine which declares the Trinity of the Creator, he is in great straits who is pressed down by earthly sorrows, seeing that from all outward delights he is commanded to abstain, and within there is no refreshment from the delight of spiritual doctrine. And yet it is effected by prayer, that he who desires should receive understanding from God, even though there be no one by whom wisdom should be preached. For it follows, And if that man shall continue, &c. The argument is drawn from the less to the greater. For, if a friend rises from his bed, and gives not from the force of friendship, but from weariness, how much more does God give who without weariness gives most abundantly whatever we ask?