The Meaning of Partisanship in the Methodology of Da'wah

Question:
The questioner says: Honorable Shaykh, may Allah grant you success, you mentioned, may Allah protect you, that the da'i takes the methodology of da'wah from the biography of the Prophet (peace and blessings be upon him) and does not take it from partisanship. What is meant by partisanship? And is it permissible for us to follow those who take their methodology from the biography of the Prophet (peace and blessings be upon him)?

Answer:
The ideological factions that form groups and establish a methodology upon which they pledge allegiance, such that they do not go beyond it, add to it, or innovate anything, and which has no basis in the Book or the Sunnah, but is merely a convention of their own; this is what is not permissible to act upon. However, if they established their methodology based on the Book and the Sunnah, and did not contradict the Book and the Sunnah, then this is a valid methodology. Yes.