Ambrose of Milan — as excerpted in the Catena Aurea on Luke 21:28-33

“Matthew speaks of the fig-tree only, Luke of all the trees. But the fig-tree shadows forth two things, either the ripening of what is hard, or the luxuriance of sin; that is, either that, when the fruit bursts forth in all trees and the fruitful fig-tree abounds, (that is, when every tongue confesses God, even the Jewish people confessing Him,) we ought to hope for our Lord’s coming, in which shall be gathered in as at summer the fruits of the resurrection. Or, when the man of sin shall clothe himself in his light and fickle boasting as it were the leaves of the synagogue, we must then suppose the judgment to be drawing near. For the Lord hastens to reward faith, and to bring an end of sinning.”