The Ruling on Using Trips and Visits as a Means of Da'wah

Question:
He says: Some people have adopted trips and visits as a method for calling young people to guidance and righteousness. What is the ruling on this in the da'wah (calling others to Islam) to Allah? And what is the ruling if teaching a book from the books of 'aqidah (creed) is combined with it?

Answer:
By Allah, I tell you: Do not leave the mosques and the congregation of the Muslims. Leave the trips and do not call them da'wah trips, because we do not know their true nature, nor who is behind them, nor who enters into them. But you have, praise be to Allah, the mosques, the schools, and the gatherings of the Muslims in their majalis (assemblies). Stick to the congregation of the Muslims; this is what I advise you to do. And because the time now is a time of fitnah (trial, discord or temptation) and a time of evils, and the Muslim has become like a sheep among wolves that want to devour him, so stick to the congregation of the Muslims and do not...