The Ruling on Cooperating with Prohibited Groups

Question:
This is a question asking: Is it permissible to cooperate with the prohibited groups and parties that are described as extremist and terrorist, such as the Tabligh and the Muslim Brotherhood in their da'wah (calling to Islam)?

Answer:
Follow the path of the righteous Salaf and the methodology of the Salaf of the Ummah and its imams, which is clear and distinct, and praise be to Allah, it is established. Follow this methodology and adhere to it, and it will protect you, by the permission of Allah, from all misguidance, from all doubts, and from all nonsense. It is a clear path; hold fast to it, as the Messenger (peace and blessings be upon him) said: And the Book of Allah and the Sunnah of the Messenger of Allah (peace and blessings be upon him) are before us, preserved, and praise be to Allah. In our hands is the weapon from the Book of Allah and the Sunnah of His Messenger against every falsehood, every doubt, every bid'ah (religious innovation), and every misguidance. The meaning of the weapon is the deadly one that scatters these falsehoods, and praise be to Allah.