37 For the coming of the Son of Man will be just like the days of Noah.
38 For as in those days before the flood they were eating and drinking, marrying and giving in marriage, until the day that Noah entered the ark,
39 and they did not understand until the flood came and took them all away; so will the coming of the Son of Man be.
40 Then there will be two men in the field; one will be taken and one will be left.
41 Two women will be grinding at the mill; one will be taken and one will be left.
42 Therefore be on the alert, for you do not know which day your Lord is coming.
43 But be sure of this, that if the head of the house had known at what time of the night the Thief was coming, he would have been on the alert and would not have allowed his house to be broken into.
44 For this reason you also must be ready; for the Son of Man is coming at an hour when you do not think He will.
This Scripture doesn't support the "rapture" nonsense but further knocks it in the head by showing the separation between believers and non-believers occurs at the Second Coming of Christ - not years before to take Christians away from the Great Tribulation/Time of Jacob's Trouble!
God will spare some from going through such a horrible ordeal, but He will protect them right here ON EARTH - not up in Heaven! (Rev. 12).
We are taught that we won't know the exact day but we will know when it is any day now - just like Noah knew and the world didn't!
Concerning the coming of our Lord and Savior, Yahshua, Christians won't be caught off guard as we are Children of the Light and not left in darkness like the world. Notice the great contrast between us and them:
1 Thessalonians 5:1-6
1 But concerning the times and the seasons, brethren, you have no need that I should write to you. 2 For you yourselves know perfectly that the day of the Lord so comes as a thief in the night. 3 For when they say, “Peace and safety!” then sudden destruction comes upon them, as labor pains upon a pregnant woman. And they shall not escape. 4 But you, brethren, are not in darkness, so that this Day should overtake you as a thief. 5 You are all sons of light and sons of the day. We are not of the night nor of darkness. 6 Therefore let us not sleep, as others do, but let us watch and be sober.
Come Lord Yahshua!