Ambrose of Milan
Catena Aurea · Lukasevangelium 17
But which of you, having a servant plowing or feeding cattle, will say unto him by and by, when he is come from the field, Go and sit down to meat? And will not rather say unto him, Make ready wherewith I may sup, and gird thyself, and serve me, till I have eaten and drunken; and afterward thou shalt eat and drink? Doth he thank that servant because he did the things that were commanded him? I trow not. So likewise ye, when ye shall have done all those things which are commanded you, say, We are unprofitable servants: we have done that which was our duty to do.
For we know that no one sits down before he has first passed over. Moses indeed also passed over, that he might see a great sight. Since then thou not only sayest to thy servant, Sit down to meat, but requirest from him another service, so in this life the Lord does not put up with the performance of one work and labour, because as long as we live we ought always to work. Therefore it follows, And will not rather say, Make ready wherewith I may sup.