Basil the Great
Catena Aurea · Lukasevangelium 13
And he went through the cities and villages, teaching, and journeying toward Jerusalem. Then said one unto him, Lord, are there few that be saved? And he said unto them, Strive to enter in at the strait gate: for many, I say unto you, will seek to enter in, and shall not be able. When once the master of the house is risen up, and hath shut to the door, and ye begin to stand without, and to knock at the door, saying, Lord, Lord, open unto us; and he shall answer and say unto you, I know you not whence ye are: Then shall ye begin to say, We have eaten and drunk in thy presence, and thou hast taught in our streets. But he shall say, I tell you, I know you not whence ye are; depart from me, all ye workers of iniquity. There shall be weeping and gnashing of teeth, when ye shall see Abraham, and Isaac, and Jacob, and all the prophets, in the kingdom of God, and you yourselves thrust out. And they shall come from the east, and from the west, and from the north, and from the south, and shall sit down in the kingdom of God. And, behold, there are last which shall be first, and there are first which shall be last.
(in reg. ad int. 240.) For as in earthly life the departure from right is exceeding broad, so he who goes out of the path which leads to the kingdom of heaven, finds himself in a vast extent of error. (int. 241.). But the right way is narrow, the slightest turning aside being full of danger, whether to the right or to the left, as on a bridge, where he who slips on either side is thrown into the river.