Christian answer: its was a forshadowing of Jesus- the lamb that was slain for the world (John 1:25)(revelation 13:8). Jesus' blood protects us from judgement the same way that the Jews were protected by the blood of the lamb from the death of the first born. It was righteousness by faith, all you had to do was believe that the blood would save you and you were saved.
Answer:
Jewish answer: It was commanded by God (Exodus ch.12). It showed that the Israelites were identifying themselves publicly as keeping God's commands and had no fear of the Egyptians and no respect for the Egyptians' idolatrous sensibilities (the lamb was one of the many things that Egyptians worshiped).
According to the book of Exodus in the Bible, the Israelites were instructed to sprinkle the blood of the Passover lamb on the doorposts and lintel of their homes as a sign for the angel of death to pass over them during the final plague in Egypt.
In the final plague in ancient Egypt, all the firstborn sons of the Egyptians were killed, while the Israelite firstborn sons were spared by following instructions to mark their doorposts with the blood of a sacrificial lamb.
The plague of blood in the Bible lasted for seven days, during which time the water in Egypt turned to blood making it undrinkable. This was the first of the ten plagues brought upon Egypt by Moses.
The Plague of darkness. From Exodus 10:21-23
We are not give the name of Pharaoh's son who was killed in the 10th plague in Egypt.
The Israelites were instructed to sprinkle the blood of a sacrificed lamb around their doors as a sign for the angel to pass over and not harm their firstborn males during the final plague in Egypt. This event is known as the Passover.
No they were all ten of them sent by god on the land of Egypt.
The second plague to hit Egypt was Frogs. The Hebrew word is Tz'fardaya.
It wasn't an angel, it was HaShem.
The tenth plague was the death of the firstborn, where God struck down all the firstborn in Egypt, from the firstborn of Pharaoh to the firstborn of the prisoner in the dungeon and even the firstborn of all the livestock. This plague finally convinced Pharaoh to let the Israelites leave Egypt.
The plague that killed Egypt's firstborn was the tenth and final plague in the biblical story of Exodus. It was known as the plague of the death of the firstborn, where all firstborn children in Egypt, including animals, were said to have died. This event ultimately compelled Pharaoh to release the Israelites from slavery.
After his son died in the Tenth Plague (death of the first-born), Pharaoh "expelled" the Israelites from Egypt (Exodus ch.12), essentially granting the demands of Moses.