Philadelphia - Trusting the Lord who opens doors

The letter from Jesus Christ to the church at Philadelphia is the only one without criticism. The town was the only town to survive the fall of the Roman Empire, and the church was the only one to survive to modern times. What can we learn from this commendation? Are we willing to trust the Lord and Head of the Church to open doors for us? Are we too quick to write our churches off as weak and ineffective?