8. What is the reason THAT THEY MARKED THE BLOOD OVER THE DOOR LINTEL AND THE TWO SIDE POSTS? It has already been explained. It is because it is a holy mark, and the Angel of Destruction had mercy upon Yisrael when he saw this blood that was marked on the opening. This is what is written: "Hashem will pass over the door..." (Ibid.). We must look closely here. If the Holy One, blessed be He, and no other messenger came and slew in the land of Egypt, what is the purpose of this mark over the door opening, since all is revealed to Him? In addition, what is the meaning of: "and will not allow the Destroyer" (Ibid.), WHICH MEANS IT WAS A MESSENGER? It should have said, 'and will not destroy.'