In the towns and villages of Judea, houses typically had an outside staircase or ladder leading up to the roof. The roof was a place for meals and entertainment. Jesus is saying that believers should make haste to escape from Judea when they see the abomination that causes desolation standing in the holy place. There will be no time to take a small detour and go into the house.1 Life matters more than basic necessities.2
17 que celui qui sera sur le toit ne descende pas pour prendre ce qui est dans sa maison;