What was the relationship between Jesus and John the Apostle?

Jesus called John, and John was one of the three who went up a high mountain with Jesus. Matthew 4:21-22; Matthew 17:1

What the Bible says

Matthew 17:1

And after six days Jesus taketh unto him Peter and James, and John his brother, and bringeth them up into a high mountain apart:

Douay-Rheims Bible (Challoner revision), public domain.

John and James were fishing partners of Simon Peter. Luke 5:10

John was in the boat with his brother James and their father when Jesus called him. Matthew 4:21-22

Later, Jesus took Peter, James, and John up a high mountain. Matthew 17:1

There they saw him change: his face shone like the sun. Matthew 17:2 How would you tell it, if you had been there?

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