Augustine of Hippo — as excerpted in the Catena Aurea on Luke 17:5-6

“(de Quæst. Ev. lib. 2. qu. 39.) We may indeed understand that they asked for the increase of that faith by which men believe in the things which they see not; but there is further signified a faith in things, whereby not with the words only, but the things themselves present, we believe. And this shall be, when the Wisdom of God, by whom all things were made, shall reveal Himself openly to His saints face to face.”