Since the beginning of time animals have been used in God's plan for forgiveness, reconciliation, and remedy for sin.
In Genesis 3 God sacrificed animals for their skin (clothing) because of Man’s original sin.
We see in Genesis 22 Abraham being instructed to sacrifice his son Isaac only to be stopped. God provided a substitutional death by a ram who was sacrificed.
Exodus 12 tells us about the Passover Lamb. It represents deliverance from death and freedom from slavery.
Sheep is a name God uses throughout the Bible for man. A prophetic word is found in Isaiah 53:6, We all, like sheep, have gone astray, each of us has turned to our own way; and the Lord has laid on him the iniquity of us all.
John the Baptist called Jesus the Lamb of God who takes away the sins of the world. That's why He came to earth because of God's great love.
Thank you Jesus for becoming a "sheep" and taking our place.