After John was arrested, Jesus went to Galilee preaching the Message of God:
"Time's up! God's kingdom is here. Change your life and believe the Message."
Passing along the beach of Lake Galilee, he saw Simon and his brother Andrew net-fishing. Fishing was their regular work.
Jesus said to them, "Come with me. I'll make a new kind of fisherman out of you. I'll show you how to catch men and women instead of perch and bass."
They didn't ask questions. They dropped their nets and followed.
A dozen yards or so down the beach, he saw the brothers James and John, Zebedee's sons. They were in the boat, mending their fishnets.
Right off, he made the same offer. Immediately, they left their father Zebedee, the boat, and the hired hands, and followed.