Matthew 24:44

Therefore, do you also prepare, since it is just when you are least expecting him that the Son of Man will come.

Luke 21:34

Be on your guard lest your minds should ever be dulled by debauches or drunkenness or the anxieties of life, and lest 'That Day' should come suddenly upon you, like a snare.

1 Thessalonians 5:3

When people are saying 'All is quiet and safe,' it is then that, like birth-pains upon a woman with child, Ruin comes suddenly upon them, and there will be no escape!

Treasury of Scripture Knowledge

Summary

And there came against Gibeah ten thousand chosen men out of all Israel, and the battle was sore: but they knew not that evil was near them.

General references

Bible References

Knew not

Matthew 24:44
Therefore, do you also prepare, since it is just when you are least expecting him that the Son of Man will come.
Luke 21:34
Be on your guard lest your minds should ever be dulled by debauches or drunkenness or the anxieties of life, and lest 'That Day' should come suddenly upon you, like a snare.
1 Thessalonians 5:3
When people are saying 'All is quiet and safe,' it is then that, like birth-pains upon a woman with child, Ruin comes suddenly upon them, and there will be no escape!

General references

Matthew 24:39
Taking not notice till the flood came and swept them one and all away; and so will it be at the Coming of the Son of Man.