1 Timothy 6:1

And they that have believing masters
That believe in one God, in opposition to the Gentiles, that held many gods, and in Jesus Christ, in distinction from the Jews; who believed in him with the heart, and professed him with their mouths, and held the mystery of faith in a pure conscience. What is said before, is said to servants that had unbelieving masters; who would be ready to blaspheme, should they act amiss. Servants were under a snare both ways, through the insinuations of false teachers; who suggested, that their servitude was not consistent with their Christian liberty; that they ought not to serve wicked men, because being called of God, they were advanced above them; nor good men, because they were upon a level with them. But the apostle teaches another doctrine;

let them not despise [them], because they are brethren;
of the same family named of Christ, and of the same household of God, and of faith, and have the same father; for though with regard to spiritual blessings, privileges, and ordinances, they were equal; yet not with regard to temporal and civil affairs; and therefore should not treat them with less respect, or be more backward to obey their lawful commands, on that account:

but rather do [them] service;
more heartily, and with a greater good will, as to the Lord; these masters belonging to him, and being engaged in his cause; which they, their servants, by yielding a cheerful obedience to them, are assisting in: and the rather,

because they are faithful;
in lesser things, in giving to them, their servants, what is just and equal, proper food and suitable raiment, and their just wages; and in using their wealth and riches in a good way, for the interest of Christ, the assistance of the poor saints, and the spreading of the Gospel; and so in greater things, by holding fast the profession of their faith, adhering to Christ, his truths and ordinances: or "because they are believing, or believers"; it is the same word as before used; and therefore they should be precious to them, and high in their esteem; for faith is a precious grace, and such as have it are chosen of God, and precious:

and beloved;
of God, who had chosen them to salvation; and of Christ, who had redeemed them by his blood; and of the saints, who are taught of God to love one another; and this is another reason why they should be served, and not despised; and a third follows:

partakers of the benefit;
of the free grace of God; of redemption and salvation by Jesus Christ, and of all spiritual blessings in him; and therefore should serve them the more cheerfully. The Syriac version renders it, "such as enjoy rest in", or "are refreshed by their service"; or "by their service to them", as the Arabic version: the sense is, that when believing servants serve their believing masters readily and faithfully, their masters are well pleased with them, delight in their service, and consider it as a benefit to them, and a kindness done them; and which therefore should animate and encourage them to serve them. Some understand these characters of

faithful and beloved,
of the servants' themselves; that because they are such; therefore they should serve, and not despise their believing masters; and particularly the last clause, which may be rendered, "who in return receive a benefit from them", as food, raiment, and wages; and besides, they are used with humanity and kindness, and in a manner becoming Christians; to which agrees the Ethiopic version, which renders it, "who will receive and help you"; will take care of you, and assist you, and supply you with what is proper and necessary:

these things teach and exhort;
the Syriac and Arabic versions add them; the servants. The apostle was not above instructing and exhorting persons of such a capacity, and in so low a state of life; and it became Timothy to do so likewise; and every minister of the word.