Paul is always eager to share the Gospel. Paul is before King Agrippa and Festus.
Paul's background as a Pharisee gave him a good background to reach his fellow Jews. He, like them, often missed the truth about Jesus (26:11). Paul could see the change that Jesus made in his life. (v15-18). Paul has a new commission (v19-24) to proclaim the message which had it origin in the teaching of Moses.
It is too much for Festus (v24). He concludes Paul is mad.
Addressing Agrippa, he asks, 'Where do you stand'. (v27). This is too confronting for the King, and so Agrippa laughs it off. (v28). Paul is patient with Agrippa (v29).
Both men find Paul innocent. But Paul's appeal to Caesar is a problem. God's plan for Paul was going to be fulfilled, and Paul wanted to do that regardless of personal cost.
Jesus likewise innocently suffered to fulfil God's plan. God's grace is always sufficient, if we are in the centre of God's will.
