While in Egypt, Israelites were to slaughter a lamb and mark their doorpost with its blood.
But why the doorpost? In Deu 6:9 Israel is commanded to write God’s commandments on their doorposts. (Also Deu 11:20)
Christ is our Pesach lamb. Also, Jesus said:
Verily, verily, I say into you, he that entereth not by the door into the sheepfold, but climbeth up some other way, the same is a thief and a robber. But he that entereth in by the door is the shepherd of the sheep. I am the door; by Me if anyone shall enter in, he shall be saved (John 10:1, 2, 9 KJV)
Jesus Christ is thus also the door. Through a door we enter our home, and once inside we are protected. Through Christ we enter the sheepfold, and we shall be saved. The Israelites who marked their door with the blood gained protection while inside their homes.
Rahab’s home became a sanctuary during the fall of Jericho.
Behold, when we come into the land, thou shalt bind this line of scarlet thread in the window which thou didst let us down by: and thou shalt bring thy father, and thy mother, and thy brethren, and all thy father’s household, home unto thee. (Josh 2:18)
The window was the entrance or exit to the home for the scouts of Israel so it functioned as a doorpost, and we can imagine the thread had to be red because it represents Christ’s blood. All who were in that home were protected on the day of Jericho’s fall, just like that time in Egypt.
What is the modern day application of this? All who enter by the door that is Christ will be saved.
Scriptural Wanderlust 