NET
16 As he went along the Sea of Galilee, he saw Simon and Andrew, Simon’s brother, casting a net into the sea (for they were fishermen).
Darby
16 And walking by the sea of Galilee, he saw Simon, and Andrew, [Simon's] brother, casting out a net in the sea, for they were fishers.
KJV
16 Now as he walked by the sea of Galilee, he saw Simon and Andrew his brother casting a net into the sea: for they were fishers.