Augustine of Hippo — as excerpted in the Catena Aurea on Luke 11:5-8

“(Serm. 105) But what are these three loaves but the food of the heavenly mystery? For it may be that one has had a friend asking for what he cannot supply him with, and then finds that he has not what he is compelled to give. A friend then comes to you on his journey, that is, in this present life, in which all are travelling on as strangers, and no one remains possessor, but to every man is told, Pass on, O stranger, give place to him that is coming. (Ecclus 29, 27.) Or perhaps some friend or yours comes from a bad road, (that is, an evil life,) wearied and not finding the truth, by hearing and receiving which he may become happy. He comes to thee as to a Christian, and says, “Give me a reason,” asking perhaps what you from the simplicity of your faith are ignorant of, and not having wherewith to satisfy his hunger, are compelled to seek it in the Lord’s books. For perhaps what he asked is contained in the book, but obscure. You are not permitted to ask Paul himself, or Peter, or any prophet, for all that family is now resting with their Lord, and the ignorance of the world is very great, that is, it is midnight, and your friend who is urgent from hunger presses this, not contented with a simple faith; must he then be abandoned? Go therefore to the Lord Himself with whom the family is sleeping, Knock, and pray; of whom it is added, And he from within shall answer and say, Trouble me not. He delays to give, wishing that you should the more earnestly desire what is delayed, lost by being given at once it should grow common.”