Therefore watch,.... Meaning both over themselves, and the flock; to prevent, if possible, false teachers entering in, and to nip the buds of heresy and schism, as soon as they appear, and to preserve themselves, and the church, from being carried away with the error of the wicked.
And remember that by the space of three years; reckoning from his first coming to Ephesus, unto this time, that he now called at Miletus; see Ac 18:19 andI ceased not to warn everyone night and day with tears; that is, he was constantly and continually cautioning them against false teachers, and their doctrines, in the most tender and affectionate manner; shedding tears at the thoughts of what mischief would be done, and how many souls would be ruined by them; which gives a lively idea of the apostle, and his ministry, of his affection, zeal, and diligence, very worthy of the imitation of all the preachers of the Gospel.