1 Thessalonians 5:2

for yourselves have known thoroughly that the day of the Lord as a thief in the night doth so come,

2 Peter 3:10

and it will come -- the day of the Lord -- as a thief in the night, in which the heavens with a rushing noise will pass away, and the elements with burning heat be dissolved, and earth and the works in it shall be burnt up.

Revelation 3:3

'Remember, then, how thou hast received, and heard, and be keeping, and reform: if, then, thou mayest not watch, I will come upon thee as a thief, and thou mayest not know what hour I will come upon thee.

Revelation 16:15

lo, I do come as a thief; happy is he who is watching, and keeping his garments, that he may not walk naked, and they may see his unseemliness,' --

Matthew 24:42-44

'Watch ye therefore, because ye have not known in what hour your Lord doth come;

Matthew 25:13

'Watch therefore, for ye have not known the day nor the hour in which the Son of Man doth come.

Mark 13:34-35

as a man who is gone abroad, having left his house, and given to his servants the authority, and to each one his work, did command also the porter that he may watch;

Luke 12:39-40

'And this know, that if the master of the house had known what hour the thief doth come, he would have watched, and would not have suffered his house to be broken through;

Jeremiah 23:20

The anger of Jehovah doth not turn back Till His doing, and till His establishing, The thoughts of His heart, In the latter end of the days ye attend to it With understanding.

1 Corinthians 1:8

who also shall confirm you unto the end -- unblamable in the day of our Lord Jesus Christ;

Treasury of Scripture Knowledge

Summary

For yourselves know perfectly that the day of the Lord so cometh as a thief in the night.

General references

Bible References

Know

Jeremiah 23:20
The anger of Jehovah doth not turn back Till His doing, and till His establishing, The thoughts of His heart, In the latter end of the days ye attend to it With understanding.

General references

Matthew 24:36
And concerning that day and the hour no one hath known -- not even the messengers of the heavens -- except my Father only;
Luke 12:39
'And this know, that if the master of the house had known what hour the thief doth come, he would have watched, and would not have suffered his house to be broken through;
Luke 17:27
they were eating, they were drinking, they were marrying, they were given in marriage, till the day that Noah entered into the ark, and the deluge came, and destroyed all;