This is the story when Jesus picks up the fishermen that he wants for disciples. In Matthew, Mark & Luke they quote Jesus as saying
"come with me and be fishers of men"
Interestingly especially considering the story in Luke of what has just happened they put aside their whole business and do so (In Luke they have just landed the biggest catch they have ever had, and they don't even try to profit from that before going off with Jesus). This speaks volumes to me, I know that I would have real problems just getting up and leaving my job, and I have no idea how these guys do it, especially as they have only just met Jesus. As down to earth type guys who have been fishermen all their lives you figure that Jesus must have made a really good impression to be this effective. Also we don't hear any complaints from Zebedee (James & John's Dad), so I figure that Jesus had the same impression on him (he just knew that as he had a family to support and wasn't single like the other guys, that God needed him elsewhere) Hmmm does this speak to how missionaries, and full time ministers should work now? Not from the point of view that they should all be single, just that God will only call those who can support their family at the same time by doing so. Probably not, I could well be reading way too much into it.
Finally in John Jesus tells us that Simon is renamed to Cephas/Peter which means rock.
This brings the count of disciples to four.