The Christians understand the four creatures to be Christ.
The Lion which is known as the king of beasts symbolizes Christ being the “King of Kings”.
The Calf which is often used for a sacrifice represents Christ being the “Sacrifice” for the sins of the humans. In the Gospel of Mark, Christ is mentioned as the servant who, for the sake of men, was to be sacrificed.
The third creature which had the face of a man portrays Christ being a man.
The Eagle which is a symbol of supremacy and sovereignty represents Christ being a deity as the Son of God.