"In the populous city of Antioch, Paul found an excellent field of labor. His learning, wisdom, and zeal exerted a powerful influence over the inhabitants and frequenters of that city of culture; and he proved just the help that Barnabas needed. For a year the two disciples labored unitedly in faithful ministry, bringing to many a saving knowledge of Jesus of Nazareth, the world's Redeemer. AA 156.4"
"And when he had found him, he brought him unto Antioch. And it came to pass, that a whole year they assembled themselves with the church, and taught much people. And the disciples were called Christians first in Antioch."
Both passages discuss Paul and Barnabas teaching in Antioch for a year. EGW expands on the details of their ministry.