▼ The day of the Lord is the period of time in the future when the Lord will intervene in the events of this earth to consummate his redemption and his judgment (Isa 2:11–12; 13:6–13; Ezek 30:3; Joel 1:15; 2:32; 3:18; Amos 5:18–20; Obad 15–17; Zeph 1:7–18; 2:2–3; Zech 14:1, 13, 20–21; Mal 4:1, 5; 1 Cor 1:8; 5:5; 2 Cor 1:14; 2 Thess 2:2; 2 Pet 3:10). It includes both blessings and curses, though the latter is emphasized here.

▼ Jesus used a thief coming at night as an illustration of the unexpected and hostile nature of the coming of God’s judgment in the future. This is repeated in various ways in v. 4; 2 Pet 3:10; Rev 3:3; 16:15.