“A pastor’s life should be vocal; sermons must be practised as well as preached.
Though Noah’s workmen built the ark, yet themselves were drowned. God will not accept of the tongue where the devil hath the soul.
Jesus did “do and teach,” (Acts 1:1). If a man teach uprightly and walk crookedly, more will fall down in the night of his life than he built in the day of his doctrine.
Now, as to the completing of the exemplary life of a minister, it is required that the principle of it be that of the life of Christ in him, (Gal. 2:20), that when he hath taught others he be not himself “a cast-away,” (1 Cor. 9:27); with which he hath a spiritual understanding, and light given him into the counsel of God, which he is to communicate, (1 John 5:20; 1 Cor. 2:12, 16; 2 Cor. 4:6, 7);—and that the course of it be singular, (Matt. 5:46, Luke 6:32); where unto so many eminent qualifications of the person and duties of conversation are required, (1 Tim. 2:2–7, Titus 1:6–9);—and his aim to be exemplar to the glory of God, (1 Tim. 4:12).
So is their general course and the end of their faith to be eyed, (Heb. 13:7).
And their infirmities, whilst really such, and appearing through the manifold temptations whereunto they are in these days exposed, or imposed on them through the zeal of their adversaries that contend against them, [are] to be covered with love, (Gal. 4:13, 14).
And this men will do when they conscientiously consider that even the lives of their teachers are an ordinance of God, for their relief under temptations, and provocation unto holiness, zeal, meekness, and self-denial.”
–John Owen, The Works of John Owen, Volume 13: Ministry in Fellowship (ed. William H. Goold; Carlisle, PA: Banner of Truth, 1850-53/1997), 13: 57-58.