Paul continued his testimony by telling his Jewish listeners that he previously opposed the gospel, just as they were doing at that time. This let them know that he understood their motives.

And I persecuted the followers of the Way, hounding some to death, arresting both men and women and throwing them in prison. 5  The high priest and the whole council of elders can testify that this is so. For I received letters from them to our Jewish brothers in Damascus, authorizing me to bring the Christians from there to Jerusalem, in chains, to be punished. Acts 22:4-5 (NLT)  

If people are meeting us for the first time, they have no context for understanding how Christ has impacted our lives. It can be helpful for us to relate what we were like before we became followers of Christ. This is especially important if we are speaking to someone with whom we share a common background. Our listeners can profit from knowing that we were not always as we are today.

Sharing our “back story” is another way for us to establish common ground with our listeners and sets the stage for relating how Christ intersected and transformed our lives.

People may argue with our doctrine and conclusions, but they cannot deny our personal story. This sets us up to share the gospel as the “how” and “why” for this transformation.