The Gospel reading on Sunday is about the call of the first disciples. I've always found it rather difficult that all Jesus has to do is walk past and say 'follow me' and these men drop everything and go. It's not just that it seems implausible, but also that they don't even appear to know who or what Jesus is before they're following him all over the place.
But it appears different in the context of all four Gospels. Last Sunday's Gospel was from John in which John the Baptist sends Andrew (who collects Peter on the way) to go and visit Jesus. Matthew's Gospel is clear that the calling of the men from their nets happens after John was arrested. So it appears that they already knew Jesus and what he was about and the call on the lake was more 'it's time for us to start'. It's as if the arrest of John the Baptist was the sign for Jesus to start his own ministry. This makes the first disciples into something like a sleeper cell - already identified and briefed, but waiting for the right time to start.
Of course, they still had to take the risk that this was the man to follow, and that his cause was the cause on behalf of which they would give up everything. That still amazes me and puzzles me, even as I try to imitate them.