Matthew 24:50
The master of that servant, will have come, on a day when he is not expecting, and in an hour when he is not observing, -
Matthew 24:42-44
Be watching, therefore, for ye know not, on what manner of day, your Lord is coming.
1 Thessalonians 5:2-3
For, ye yourselves, perfectly well know - that, the day of the Lord, as a thief in the night, so, cometh;
Revelation 3:3
Remember, therefore, how thou hast received, and didst hear, and keep it and repent. If then thou shall not watch, I will have come as a thief, and in nowise shalt thou get to know, during what sort of hour, I will have come upon thee.
Proverbs 29:1
He that being often reproved stiffeneth his neck, suddenly shall be hurt, and there be no healing.