Matthew 24:37

And as were the days of Noah, so shall be the coming of the Son of man. For as in those days which were before the flood they were eating and drinking, marrying and giving in marriage, until the day that Noah entered into the ark. And they knew not until the flood came, and took them all away; so shall be the coming of the Son of man. Then shalt two men be in the field; one is taken, and one is left: two women shall be grinding at the mill; one is taken, and one is left.

A number of similarities between conditions prior to the flood and those before the final judgment may be noted. The vast majority will have rejected God's word. There shall be no awareness of impending disaster. The normal pursuits of mankind will continue, as always. Ignorance of God and of his designs for mankind will continue up to the very hour of judgment; and the righteous shall continue to live in close proximity to the wicked until the very last. No thought of judgment or of reckoning shall disturb the minds of people; and THEN it will occur suddenly, universally, in a single day, and at a time when men shall least expect it. No wonder, therefore, that the admonition to "watch" was made a part of the discourse. The men in the field and the women at the mill show that no separation between the righteous and unrighteous shall be made until judgment.