"Greetings Appellos, approved in Christ." Romans 16. 10
If today we ask a hundred Christians taken at random : "Who knows Appellès and what do you know ? How many will remember his name and know what characterized this brother of Rome ? And yet what a magnificent eulogy he receives from the apostle Paul : "approved in Christ" or, according to another version, "who has proved himself in Christ" ! The Greek word dokimos (approved, tested) was used at the time for precious metals, such as gold and silver, which had been checked for purity.
Generally commentators insist on some of Paul's greetings to the Romans, the one where the apostle comments on their activities or what they are about him, relatives or friends. Appellès escapes these two categories and is not mentioned anywhere else in Scripture. He is obviously one of the "almost unknown people in Rome", as the reformer Calvin refers to those whom the apostle mentions only by name. So what did he do to deserve the Lord's approval ?
The silence of the Word on this subject allows us to say that it is less important for us to know what it has done than to know that the Lord has approved it ; for Appelles probably deserved the Lord's approval by his manner of serving him and bearing witness to him.
This is confirmed by Paul's exhortation to Timothy : "Study to present yourself to God, approved (dokimos), a workman who does not have to be ashamed" (2 Tim 2:15) . The same goes for every Christian in particular. It is in his daily behavior, with his people first, then around him, in his conduct in every circumstance, that he is exhorted to deserve the approval of God. To suppose that the approval of God is reserved for the great gifts of a prophet, a doctor, a pastor, or an evangelist, or even an eminent public ministry, would be a grave mistake. The example of Appellès proves it ; this approval was granted to a simple member of the Church in Rome of whom nothing else is known. But what an encouragement for this man at the time of the public reading of Paul's letter ! What encouragement also for us in this example : the Lord takes note of all that is done for him, he appreciates and remembers (Matt 26. 10-13) ! "Whatever you do, in word or deed, do everything in the name of the Lord Jesus" (Col. 3:17).
Source (Pleasing the Lord)