For you yourselves know well that the day of the Lord comes like a thief in the night.
The phrase "the day of the Lord" also refers to the Second Coming of Christ (cf. Joel 3:9-16; Zechariah 14:1-5; Revelation 16:12-16; Revelation 19:11-21); it includes that event between the Tribulation and the Millennium. Thus Scripture uses the term in a broad sense (the Tribulation and the Millennium) and a narrow sense (the return of Christ).