Other Answers (12) I believe Jesus knew how He was going to die, and the reason for it, by the time he was 12 years old. When He was 12, He was already at the synagogue, teaching the elders what He knew. Surely by then He knew what His destiny was.. Well, we don't know exactly but it was long before it happened because Jesus tried to tell his disciples but they didn't understand him. It may have been really early at the time when we read of Jesus at the age of twelve having got left behind at the Temple in Jerusalem. His mother Mary and guardian Joseph had thought that Jesus was with other members of the family who had gone up to Jerusalem and returned and when they couldn't find him they returned searching for him. After a few days they found him in the Temple listening to and questioning the Teachers there. It is recorded that they were astonished at Jesus' understanding of the Old Testament Scriptures which speak of his suffering. When Jesus was baptised in the River Jordan by John the Baptist he received the power of the Holy Spirit, God's power and I feel sure that he would then have really understood the significance of all that his Heavenly Father wanted him to do. They were taken out of their cells and told that they were going to be crowned King of the Jews and they felt they were being set free for