In this scripture, Paul chose to focus primarily on the great work within that "Wide open door", rather than those who opposed him.
Great opportunities are often accompanied by great opposition. Unfortunately, the easiest thing to do when confronted with opposition is to give up.
However, when you begin to walk through that great open door, it is crucial to your ministry and to others, that you keep going, no matter what is in the way, no matter what threatens to prevent you from doing what you have been called to do. Your suffering does not excuse you from your call.
The most fascinating thing about the opposition you encounter when you walk through those open doors, is that the criticism, the anger, the ridicule, the questioning, the sarcasm, the treachery, the threats, the name calling, the backbiting, the curses, the doubting, of not only your abilities, but your calling as well as your ministry, is that opposition is prompted by your progress.
When God opens up a great door of opportunity, and you began to walk through that door, what you have just done is walked straight into the center of His Will.