For yourselves know perfectly that the day of the Lord so cometh as a thief in the night.
As a thief in the night. The apostles follow their Lord's parable, expressing how His coming shall take men by surprise (Matthew 24:43; 2 Peter 3:10). 'The night is wherever there is quiet unconcern' (Bengel). "At midnight" (perhaps figurative: to some parts of the earth it will be literal night), Matthew 25:6: cf. Luke 17:31, "in that day;" Luke 17:34, "in that night." The thief not only gives no notice of his approach, but takes all precautions to prevent the household knowing of it. So the Lord (Revelation 16:15). Signs will precede, to confirm the patient hope of the watchful; but the coming itself shall be sudden at last (Matthew 24:32-36).
Cometh. - present: expressing its speedy, awful certainty.