Biblical explanation - The Book of Revelations

Mark 13

Mark 13:14-16 (KJV)

14 But when ye shall see the abomination of desolation, spoken of by Daniel the prophet, standing where it ought not, (let him that readeth understand,) then let them that be in Judæa flee to the mountains:

15 and let him that is on the housetop not go down into the house, neither enter therein, to take any thing out of his house:

16 and let him that is in the field not turn back again for to take up his garment.