As he walked by the Sea of Galilee, he saw two brothers, Simon, who is called Peter, and Andrew his brother, casting a net into the sea—for they were fishermen. And he said to them, "Follow me, and I will make you fish for people." Immediately they left their nets and followed him.
Matthew 4:18-22
The calling of the first Disciples marks the beginning of Jesus' ministry, following his baptism by John the Baptist, and the time of testing by Satan in the desert.
It is interesting to contemplate how we might have reacted had we lived during that time and been asked to leave everything and follow Jesus. But this was a time chosen by God, and people chosen by God for a specific purpose. Even though the Disciples got to walk and talk with Jesus directly, ask him questions and learn from him, it does not appear that they had an easy time understanding. In fact, it seems like it wasn't until all the facts were in, the life and teaching of Jesus, His death, and witness of His resurrection and ascension that they truly understood. Their willingness to move from denial to a belief so strong that they were themselves crucified, offers compelling proof that all these events occurred.
Sometimes we are so busy looking for proof that we don't see it all around us. Most often it is only by the grace of God that we can a see the truth. Even though we did not live during the time of Jesus, it is true that we are being, called just as the Disciples were called, to follow Jesus. Are we listening? Are we responding?
Warren Harper (2011)