Remember therefore how (or, after what sort) thou hast received and heard (or, didst hear — the tense changes). — Remembering that the words are addressed primarily to the angel himself, the change of tense may have been designed to point him back to some particular period of his life, such as the time when he was set apart to his ministerial work. The further expectation is to hold fast, or keep — i.e., as an abiding habit. It has been noticed that this counsel is identical with that given to Timothy to “keep the good thing which had been committed to his charge” (2 Timothy 1:14; comp. also 2 Timothy 2:2). “Repent” is the closing word; combined with the exhortation to hold fast, it reminds us that formal tenacity of truth and a fruitless inactive regret are alike useless. There must be the sorrow for the past, and a sorrow which shows itself in action — a repentance whereby sin is forsaken. (Comp. Revelation 2:5; Revelation 2:21.)
If therefore thou shalt not watch. — Better, If thou shalt not watch (or, have been awake), I will come (omit “on thee”) as a thief, and thou shalt not know what hour I will come upon thee. The warning is an echo from the Gospels (Matthew 24:42-43; Luke 12:39-40). The coming of Christ to judge His Church would be in an hour unlooked for. What kind of hour He would so come was’ unknown; the sound of His approaching footsteps unheard. Shod with wool, according to the ancient proverb, stealthily as a thief, the Judge would be at the door. Yet they could not plead that they had been in darkness (1 Thessalonians 5:4).