How do we know that Peter was called by grace?

Peter's calling is a theological reflection of God's grace, specifically detailed in John 1:40-42. Initially, it is his brother Andrew who, after hearing John the Baptist speak of Jesus, actively seeks out Peter to bring him to Christ. Upon meeting him, Jesus names him Cephas, or Peter, indicating a destiny beyond his current life as a fisherman. This act illustrates that God's call is not based on human merit but rather on divine purpose and grace. Additionally, the effectual nature of this call is evident as Peter responds without hesitation, leaving his nets to become a disciple of Jesus. Such a calling emphasizes both the role of human agency in responding to God's call and the overwhelming nature of God’s grace in initiating that relationship.