Peter was extremely protective of his Master and cut off the ear of the servant of the high priest who was in the group sent to capture Jesus ahead of his execution. Jesus showed Peter that violence was not the answer by immediately healing the man’s ear.
As Peter’s fears got the better of him, he followed up his attack on the servant by then betraying Jesus, denying three times that he was one of His master’s disciples after Jesus was captured. But Jesus even forgave this cowardly act. After his resurrection from the dead, Jesus spoke to Peter and seeing his disciple’s repentance he called on him to take care of his “sheep” - those that would come to believe in Him.
To Peter’s credit, He accepted the second chance and the second life that Jesus offered. He went on to be a very strong leader in the early church, sharing the good news of Jesus with whomever he met. Peter remained committed to Jesus the rest of His life.