The image of a nocturnal thief as divine judgment is developed from the prophets (see Jeremiah 49:9 Obadiah 1:4–6; Joel 2:9),1 and would become a major New Testament metaphor (1 Thessalonians 5:2; 2 Peter 3:10; Revelation 3:3; Revelation 16:15). The key idea conveyed is that constant readiness is required because the Son of Man can come at any moment. The owner does not know when the thief will come but he keeps watch; so also it must be with the disciples.2 They must stay awake
by living in such a manner that they are continuously ready for Jesus’ return.3
44 Therefore you also must be ready, for the Son of Man is coming at an hour you do not expect.