A: Peter, Andrew, James, and John were clearly fishermen (Mt 4:18-22)(Mk 1:16-20) (Lk 5:1-11). Matthew (Levi) was a tax collector for the hated Romans (Mt 9:9-13)(Mk 2:14-17)(Lk 5:27-32).
Based on (Jn 21:1-5), it appears that Thomas and Nathanael (Bartholomew) and “two others of His disciples” (one likely being Andrew plus either Philip, Simon, James “the less,” or Thaddaeus [Lebbaeus]) were also fishermen.
We know nothing of the occupations of the remaining four disciples. However, some conjecture that Judas Iscariot (who betrayed Jesus) may have held a previous job where he handled money (i.e. bookkeeper or accountant) since he was in charge of the money that Jesus and the disciples had (Jn 12:6)(Jn 13:29).
While not an occupation, it is believed that Simon (the zealot) (Mt 10:4) (Mk 3:18)(Lk 6:15)(Acts 1:13) was likely a member of a radical Jewish sect called “the Zealots” which were fanatical about the law and strongly opposed Roman rule.
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