Only let your conversation be as it becometh the Gospel of Christ,.... Or "behave as citizens worthy of the Gospel"; for not so much their outward conversation in the world is here intended, which ought to be in wisdom towards them that are without; so as to give no offence to any, and to put to, silence, the ignorance of foolish men, and them to confusion and: shame, who falsely accuse their good conversation in Christ; though this is what is highly becoming professors of the Gospel; and a moral conversation proceeding from principles of grace, under the influence of the Spirit of God, is very ornamental to the Gospel, being what that requires and powerfully teaches; but the conversation of the saints one with another, in their church state, is here meant.
The allusion is to cities which have their peculiar laws and rules, to which the citizens are to conform; and such as behave according to them act up to the character of good citizens, and becoming, and worthy of the charter by which they hold their privileges and immunities.
A church of Christ is as a city, and is often so called; the members of it are citizens, fellow citizens, one with another, and of the household of God, and have laws and rules according to which they are to conduct themselves; as such do who walk worthy of their calling, and becoming the charter of the Gospel by which they have and hold their freedom and privileges, as citizens of the new Jerusalem: and such a Gospel walk and conversation lies in such things as these; constant attendance on the preaching of the Gospel, and on the administration of Gospel ordinances; a strict observation of the rules of behaviour towards persons that have given offence, either in public or private; a just regard to the discipline of Christ's house, in admonitions; reproofs, censures and excommunications, as cases require; cultivating love, unity, and peace; keeping the ordinances as they were delivered; retaining and striving for the doctrines of the Gospel; holding the mysteries of it in a pure conscience, and adorning: it by a becoming life and conversation.
This the apostle recommends as the "only", the main and principal thing these saints should attend to; and as what would give him the greatest joy and pleasure to hear of, whether he should ever come and see them again or not:that whether I come and see you, or else be absent, I may hear of your affairs.