Question: "What does it mean that Jesus will return like a thief in the night?"
Answer: The return of Jesus Christ is likened to the coming of a thief in the night. Two passages use the wording “a thief in the night”: Matthew 24:43, “Understand this: If the owner of the house had known at what time of night the thief was coming, he would have kept watch and would not have let his house be broken into,” and 1 Thessalonians 5:2, “You know very well that the day of the Lord will come like a thief in the night.”
In Matthew 24, Jesus speaks of His second coming at the end of the tribulation. Paul calls it “the day of the Lord” in 1 Thessalonians 5. This is a day of divine retribution featuring astronomical upheaval and the visible “sign of the Son of Man” in the heavens (Matthew 24:29–30). Jesus says it will happen “after the tribulation of those days” (verse 29, ESV), a description that distinguishes this event from the rapture, which happens before the tribulation.
How is the second coming going to be like a thief in the night? The key element of Jesus’ comparison is that no one will know when He will return. Just as a thief catches a household by surprise, Jesus will catch the unbelieving world by surprise when He returns in judgment. People will be “eating and drinking, marrying and giving in marriage” (verse 38), just as if they have all the time in the world. But then, before they know it, Judgment Day will be upon them (verses 40–41). Paul puts it this way: “While people are saying, ‘Peace and safety,’ destruction will come on them suddenly, as labor pains on a pregnant woman, and they will not escape” (1 Thessalonians 5:3).
The believer does not fear this swift and sudden judgment; the “thief in the night” will not catch us by surprise. Christians are in a separate category: “But you, brothers and sisters, are not in darkness so that this day should surprise you like a thief” (1 Thessalonians 5:4). It is only those in darkness who will be taken unawares, and we “are all children of the light and children of the day. We do not belong to the night or to the darkness” (verse 5). Praise the Lord, “God did not appoint us to suffer wrath but to receive salvation through our Lord Jesus Christ” (verse 9).
The unsaved should heed Jesus’ warning: “Be ready, because the Son of Man will come at an hour when you do not expect him” (Matthew 24:44). How can you be ready? God has provided the way for you to escape the judgment. That way is Jesus Christ (John 14:6). By accepting Jesus as your Lord and Savior, you are granted forgiveness of sins, mercy, and salvation with the promise of everlasting life (John 3:16; Ephesians 2:8–9). The “thief” is coming, but you can be a child of the day. Don’t put it off; this is “the year of the Lord’s favor” (Luke 4:19).