1 Corinthians 16:9

For a great door and effectual is opened unto me, and there are many adversaries.

Door () - an opening for extending the Gospel. Wise men watch for, and avail themselves of, opportunities. So "door" of hope () "door of faith" (), "an open door" (), "a door of utterance." (). "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). Where great good is, evil is sure to start up its antagonist.