Shaykh Ibraheem Ar-Ruhaylee said, “Shaykh Uthaymeen in his book Sharh Lumatul Itiqaad page 110-111 stated, ‘Abandoning Ahlu Bidah is obligatory due to the statement of Allah, “You (O Muhammad (sallallaahu alayhi wasallam)) will not find any people who believe in Allah and the Last Day, making friendship with those who oppose Allah and His Messenger…” Surah Mujaadilah (58) ayat 22.
Plus the Prophet abandoned K’ab bin Maalik and his companions while they remained behind from the battle of Tabook.
But if it is an advantage to sit in their (Ahlu Bidahs) gathering to clarify the truth to them and to warn them from bidah (innovation in the religion) there is no problem in this.
Perhaps this is desired because of the statement of Allah, “Invite (mankind, O Muhammad (sallallaahu alayhi wasallam)) to the Way of your Lord (i.e. Islam) with wisdom (i.e. with the Divine Inspiration and the Qur’an) and fair preaching, and debate with them in a way that is better.””
Ref: Mawqif Ahlus Sunnah Min Ahlul Ahwaa Wal Bidah Vol 2 page 547
Posted by Abdul Kareem Ibn Ozzie