Matthew 4:18 - 22

18 And Jesus, walking by the Sea of Galilee, saw two brothers, Simon called Peter, and Andrew his brother, casting a net into the sea; for they were fishermen. 19 Then He said to them, “Follow Me, and I will make you fishers of men.” 20 They immediately left their nets and followed Him.

21 Going on from there, He saw two other brothers, James the son of Zebedee, and John his brother, in the boat with Zebedee their father, mending their nets. He called them, 22 and immediately they left the boat and their father, and followed Him.

Simon(Peter) and Andrew were professional fishermen. They had a good honest livelyhood. According to John 1:35 – 42 these two men were also followers of John the Baptist. When Jesus encountered them they were working at making a living. Casting their net into the water to try to catch a haul of fish.

These two men were already converted by John, so Jesus did not have to tell them to repent to prepare for the kingdom of heaven. John had already convinced them to “repent and be baptized” so these men were prepared to enter the work of which Jesus was inviting them and they had already been prepared. Jesus used the psychological appeal, inviting fishers of fish to become fishers of men. He was offering them spiritual meat to use for bait to catch a more valuable fish, the souls of men.

They gave up their worldly occupation for the sake of following Christ.

As he continues along the shore he encounters two more professional fishers and their father. Instead of fishing now they are taking care of the business of mending their equipment. Their father's name is Zebedee and he was a Jew who was a professional fisherman. Jesus also called his sons to follow him as fishers of men.

Verse 22 shows that along with Peter and Andrew, James and John left everything behind to follow in the work of Christ. They left their work behind to change their professions to become “fishers of men.”