2:13-17 A Christian conversation must be honest; which it cannot be, if there is not a just and careful discharge of all relative duties: the apostle here treats of these distinctly. Regard to those duties is the will of God, consequently, the Christian's duty, and the way to silence the base slanders of ignorant and foolish men. Christians must endeavour, in all relations, to behave aright, that they do not make their liberty a cloak or covering for any wickedness, or for the neglect of duty; but they must remember that they are servants of God.
16. As free—as "the Lord's freemen," connected with 1Pe 2:15, doing well as being free. "Well-doing" (1Pe 2:15) is the natural fruit of being freemen of Christ, made free by "the truth" from the bondage of sin. Duty is enforced on us to guard against licentiousness, but the way in which it is to be fulfilled, is by love and the holy instincts of Christian liberty. We are given principles, not details.
not using—Greek, "not as having your liberty for a veil (cloak) of badness, but as the servants of God," and therefore bound to submit to every ordinance of man (1Pe 2:13) which is of God's appointment.