The sign of the blood on the door meant safety to those within the houses of Israel on the dark Passover night so long ago. The firstborn in the blood-marked houses were safe when the angel of death passed over.
Traveling in an Eastern country just after terrible riots and massacres had taken place between representatives of opposing religious groups, in which Christians were not involved, I noticed crude red crosses scrawled on buildings and walls. The few Christians living there had placed this symbol of their faith upon their doors, and they were safe within.
"When I see the blood, I will pass over you" were the words of God. The apostle says, "Christ our passover is sacrificed for us" (1 Cor. 5:7). And again, "Christ died for our sins according to the scriptures" (1 Cor. 15:3). It has been said that there are 13 different theories of the atonement, but the truth in all of them is not enough to express fully the wonder and glory of our salvation through the precious blood of our Redeemer. We can never fully understand it, and it will be the subject of our study through the endless ages of eternity. We cannot see the blood in all its meaning, but what we do see is for our comfort. The Lord's sight of it secures our safety--"When I see the blood, I will pass over you."
We are justified by the blood, and when God sees that we are under its protection He will, He must, pass over us, because "he...spared not his own Son, but delivered him up for us all" (Rom. 8:32). That is our surety.
MEDITATION PRAYER: "I will rejoice in thy salvation" (Ps. 9:14).