Matthew 24:50

the master of that servant will come in a day that he doth not expect him, and at an hour which he knoweth not.

Matthew 24:42-44

Watch therefore: for ye know not at what hour your Master cometh.

1 Thessalonians 5:2-3

for yourselves know precisely that the day of the Lord so cometh as a thief in the night.

Revelation 3:3

Remember therefore how thou hast received and heard, and observe, and repent. If then thou art not found watching, I will come upon thee as a thief, and thou shalt in no wise know at what hour I will come upon thee.

Treasury of Scripture Knowledge

Summary

The lord of that servant shall come in a day when he looketh not for him, and in an hour that he is not aware of,

Bible References

Come

Matthew 24:42
Watch therefore: for ye know not at what hour your Master cometh.
1 Thessalonians 5:2
for yourselves know precisely that the day of the Lord so cometh as a thief in the night.
Revelation 3:3
Remember therefore how thou hast received and heard, and observe, and repent. If then thou art not found watching, I will come upon thee as a thief, and thou shalt in no wise know at what hour I will come upon thee.