The four Gospels present Jesus Christ in four different fashions.
Matthew’s Gospel shows Jesus Christ as King – there is the lineage given that points to Jesus Christ having a rightful claim to David’s throne, for example.
Mark’s Gospel shows Jesus Christ as Servant.
Much time is spent showing Jesus Christ in action and in service toward others.
The Gospel according to Luke points toward Jesus Christ being the Son of Man.
Again there is the lineage that points to Jesus Christ as the rightful heir to the throne of David.
And when you read John’s Gospel, you see Jesus Christ as God.
John 1:1 In the beginning was the Word, and the Word was with God, and the Word was God.
The phrase “I am” is said by Jesus Christ many times in the Gospel according to John, and especially in this passage in John chapter 18, the phrase “I am” has a greater meaning.