"They were in their boat with their father Zebedee, getting their nets ready. Jesus called them, and at once they left the boat and their father, and went with him." (Matthew 4:21)
Faith is a personal decision to follow Christ. It does not matter if you were born and raised in a devout Christian family or not. The decision had to be made. Will you choose to respond to Christ call? Jesus had already shown us the benefits of becoming his disciple.
"Faith is man's response to God, who reveals himself and gives himself to man, at the same time bringing man a superabundant light as he searches for the ultimate meaning of his life." (Catechism of the Cathelic Church #26, definitive edition, p.19)