For a great door and effectual is opened unto me, and there are many adversaries.
Door (2 Corinthians 2:12) - an opening for extending the Gospel. Wise men watch for, and avail themselves of, opportunities. So "door" of hope (Hosea 2:15) "door of faith" (Acts 14:27), "an open door" (Revelation 3:8), "a door of utterance." (Colossians 4:3). "Great" - i:e., extensive. "Effectual" - i:e., opportune for effective working. Many adversaries - who would block up the open door, whence my presence is needed to check them. Not here false teachers, but open adversaries-Jews and pagan. After Paul, by long-continued labours at Ephesus, had produced effects threatening the gains derived from idolatry, "many adversaries" arose (Acts 19:9-23). Where great good is, evil is sure to start up its antagonist.