Thousands of years ago, God appointed Mosheh as His mediator to bring an empire to its knees and to create for Himself a nation to be His honor-bearers to the rest of the world. He first completely shamed all the supposed gods of the Egyptians and then sent the destroyer out in their midst. And yet Israel, those who put the blood of a lamb upon their doorposts, was protected when YHWH pesach'ed them. It was not the blood that protected them; YHWH protected them when He saw the sign of the covenant, the blood. In the ancient Near East, blood was used in order to ratify covenants and in the Scriptures it was used to create an inseparable bond of relationship, a blood index, between two parties. The Passover was in fact a covenant where the Hebrews became adopted as the sons of God through a blood covenant. Over one thousand years later, God again sent a mediator, His own son Yeshua, who would bring the empire of the Adversary to its knees and would restore and expand the Kingdom of God to include all people who choose to accept the blood of Yeshua as a covenant, indexing them in a relationship as the sons of the Living God.
Then Moses called for all the elders of Israel and said to them, “Go, select lambs for your families and slaughter the Passover lamb. You are to take a bundle of hyssop, dip it in the blood that is in the basin, and apply it to the crossbeam and two doorposts with the blood from the basin. None of you may go out the door of his house until morning. YHWH will pass through to strike down the Egyptians, but when He sees the blood on the crossbeam and the two doorposts, YHWH will pass over that door, and will not allow the destroyer to come into your houses to strike you down. Also you are to observe this event as an eternal ordinance, for you and your children.