Acts 26 is the story of Paul speaking in his own defense before King Agrippa, the governor, Bernice (the king's sister), and others. Paul is making his appeal even though he isn't actually on trial. Paul begins humbly and with great respect. He has been imprisoned for basically two years. Now he has a great opportunity to speak. Paul shares his own personal story. Through sharing his own story, he shares the story of Christ. Paul has endured so much, but God gave him the chance to speak for Him.
It's interesting to me that Paul uses his own personal story to share Christ. We all have a story. Each of us have been on a journey that is unique to us. It's a journey that God has used to bring us to Him, and it's a journey that should draw us closer to Him through the ups and downs of life. Sharing our story...helps others so share your journey.