The answer is: John Mark

Acts 12:25

Let's take a moment to explore Paul's first missionary journey and the intriguing figure of John Mark who joined him. Paul, previously known as Saul, is one of the central characters in the New Testament. This journey marked the beginning of a transformative phase in early Christian history.

Now, John Mark wasn't just any travel companion; he had notable connections—being a cousin to Barnabas and possibly one of the early followers of Jesus. His readiness to join Paul and Barnabas reflected a strong commitment to spreading the new faith beyond Jerusalem. Fun fact: John Mark’s presence is pivotal. While he started with Paul, the lack of drama in his journey belies future complexities.

During the journey itself, which took them as far as modern Turkey, these bold missionaries faced challenges and spread the message of Christianity in synagogues and meeting places. They weren’t just preachers; they were pioneers in establishing communities based strongly on mutual support and reinforcement of faith.

Additionally, John Mark’s story didn't stop there. After various events led him to part ways with Paul, he would later reconnect and, according to tradition, even write the Gospel of Mark, spreading an important narrative of Jesus's life. This illustrates how such early travels weren't merely about geographic movement but fostered deep spiritual legacies, echoing throughout the early church and beyond. Each journey, stumble, or partnership contributed richly to a tapestry of belief that we still explore today!