Gaius

Gaius is being praised here specifically because traveling witnesses reported back that his inner life and his outward conduct were fully aligned — he was genuinely walking in the truth, not just professing it.

Gaius is listed here as one of Paul's traveling companions from Derbe — part of the multi-city team accompanying Paul on his final journey toward Jerusalem.

Gaius is identified here as the host not only of Paul personally but of the whole church — his home functioning as the base of operations from which this letter was written and dispatched.