Barnabas was "a good man, full of the Holy Spirit and of faith" (Acts 11:24a).
Although he was not one of the original twelve apostles, he was an integral part of Christianity's early growth. Barnabas, a Levite from Cyprus, was an early convert who sold a field and donated the proceeds to the apostles. They called him Barnabas because it meant "son of encouragement." He introduced Paul to the other leaders after Paul's conversion.
Barnabas went to preach in Antioch "and a great many were brought to the Lord" (Acts 11:24b). He invited Paul to join the work there; the men returned to Jerusalem after completing their mission. From there Barnabas and Paul were sent by the Holy Spirit to preach the good new in Cyprus and Asia. Both men believed in outreach to Gentiles (non-Jews) but when they had a falling out Paul continued on his missionary journey with Silas, and Barnabas was not mentioned again in the Book of Acts.
Legend has it that Barnabas was stoned to death in 61 in Salamis.
Image is detail of St. Barnabas icon, compliments of St. Isaac of Syria Skete, www.skete.com