John son of Zebedee was a disciple of Jesus. He left everything behind including his father to follow Jesus because he had evidence to believe Jesus was the Son of God. Jesus gave him the authority as a disciple to drive out demons and heal diseases. He was to shout from the roof tops what Jesus told them. John’s job was to preach to the lost sheep of Israel that the kingdom of heaven is near. John’s testimony in his gospel is part of our evidence that Jesus is the Son of God and He is worth leaving everything behind and following. According to Matthew 10:32-33 Jesus will acknowledge before the Father in heaven whoever acknowledges Him before men. John acknowedges Jesus before all men so we may believe and become disciples ourselves.
”The one who welcomes you welcomes Me, and the one who welcomes Me welcomes Him who sent Me. Anyone who welcomes a prophet because he is a prophet will receive a prophet’s reward. And anyone who welcomes a righteous person because he’s righteous will receive a righteous person’s reward.” Matthew 10:40-41