The Lord grant unto him that he may find mercy of the Lord in that day;.... In return for his diligent seeking till he found the apostle. By "mercy", he means the mercy of our Lord Jesus Christ unto eternal life; or that crown of righteousness and everlasting glory and happiness, which will be a grant from the Lord, or a free gift through Jesus Christ; the effect of pure grace and mercy, and not of merit.
The apostle does not propose to requite him himself; he knew it was out of his power; but he had an interest in the Lord, and at the throne of grace; and he makes use of that in his favour, and prays the Lord that he might find mercy of him: and the meaning is either, that he prayed to God, that he might find mercy of him; or he prayed particularly to the Lord Jesus Christ to act the part of a Mediator for him with his Father, that he might enjoy eternal life through him; or he prayed to God the Father, that he would grant that he might find mercy at the hands of Jesus Christ his Son, the Judge of quick and dead, who, at the great and last day, will give the crown of righteousness to all that love him, and his appearance:and in how many things he ministered unto me at Ephesus, thou knowest very well: or "better".
Timothy being at Ephesus, of which city Onesiphorus seems to have been, and that when the apostle was there, he very freely communicated to him, as Timothy, who was with him there, knew very well: the apostle does not forget, but remembers former kindnesses, as well as takes notice of present favours, and which shows a grateful mind.
The phrase, "unto me", is not in the Greek copies, though it is in the Vulgate Latin and in all the Oriental versions; wherefore the words may be understood of the things which Onesiphorus had ministered to Timothy, and to the church at Ephesus, and to the poor saints there; which Timothy was "better" acquainted with than the apostle could be, he being on the spot: and now since there were so many fallen off, and so few that remained hearty and faithful, but one Onesiphorus to all them that were in Asia; the apostle exhorts to firmness and constancy, in a dependence on the Spirit and grace of God, as follows.