A.T. Robertson Commentary Acts 8:40

"But Philip was found at Azotus: and passing through he preached the gospel to all the cities, till he came to Caesarea." — Acts 8:40 (ASV)

He preached the gospel (ευηγγελιζετο). Imperfect middle describing the evangelistic tour of Philip "till he came to Caesarea" (εως του ελθειν αυτον, genitive articular infinitive with the preposition εως and the accusative of general reference) where he made his home and headquarters thereafter (Acts 21:28) and was known as the Evangelist.