Luke 17:7-10
No merit in works: V. 7. 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; V. 8. 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? V. 9. Doth he thank that servant because he did the things that were commanded him? I trow not.
V. 10. 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.
Since faith, according to the Lord's own explanation, shows itself in good works, in deeds of mercy and forgiveness and other miraculous acts such as are impossible without faith, the thought might have arisen in the hearts of the disciples that works were therefore meritorious, that they earned something in the sight of God. But this thought the Lord precludes by a parabolic narrative, a parallel with strong application.
“Christ's purpose is not to teach in what spirit God deals with His servants, but to teach rather in what spirit we should serve God.” If a master has a slave that has been plowing or doing the work of a herder out in the field, and this servant comes home in the evening, he will not say to him: Go at once and get your supper.
The master will continue to require the services of the slave, bidding him first prepare the supper for the master, then gird up his clothes about him and wait at the table. After the lord of the house has eaten and drunken, then the slave may also have his supper. The master would not think of thanking the slave for the work he has thus performed, for the service was taken as a matter of course; it was all in the day's work. The picture is not too harsh or overdrawn, but is taken from conditions which were usual in the time of Christ throughout the Roman Empire.
Now the Lord makes the application, saying that even so all believers, when they have done all that they were commanded to do, which includes all the demands which grow out of all situations confronting men at all times, when they have done their full duty (if that were possible), yet they will have nothing to boast of, nothing for which they could demand anything of God in return. They are still unprofitable servants; they have but done that which was expected of them as their duty.
There is no merit or worthiness before God in them even then. If God looks upon the good works of the Christians with a kindly countenance and praises and rewards them, that is not a matter of merit, but of free grace. All the greater is our obligation of love.