Paul’s defence before King Agrippa is described in Acts chapter 26. Paul tells of his upbringing and early life as a strict Pharisee, of his opposition to the followers of Jesus, and of his journey to Damascus with the intention of persecuting Christians. He then tells of his heavenly vision and encounter with Jesus, and how in the vision Paul was given the mission of being a witness for Jesus to many people.
It is interesting to observe the effect of what Paul said on his listeners. Governor Festus said, “Paul, you are crazy! Too much studying is driving you insane!” King Agrippa said, “Are you trying to make me a Christian so quickly?” The responses indicated that both listeners were feeling the magnetic pull of what Paul was saying. Something about the passion with which Paul spoke and the way the Holy Spirit was working through him made the listeners contemplate the possibility that what he said might be true.
There is always a similar moment of spiritual magnetism when someone first encounters Jesus. Evangelism is never solely an intellectual exercise in presenting the logical reasons for the existence of God. We like to rationalise our decisions as if they were made based solely on the facts, but a decision to believe that God really does exist and that Jesus is who he claims to be is an emotional and spiritual decision as well as a rational decision.