Allaah (The Most High) said:
وَلَا تَرۡكَنُوٓاْ إِلَى ٱلَّذِينَ ظَلَمُواْ فَتَمَسَّكُمُ ٱلنَّارُ
”And incline not toward those who do wrong, lest the Fire should touch you.”
[Hud: Ayah 113]
[The word (ظلم –wrong) in (this ayah) can (mean) disbelief; it can (mean) bidah and it can be (فسوق i.e. sinful-immoral behaviour) because (ظلم) is applicable to all these types of (affairs). So we refrain from inclining towards the evil doers, the people of bidah, the disbelievers, the secularists and other than them. And we protect ourselves, our Aqeedah and that which Allaah has bestowed upon us of Imaan and sound religion.
It is sufficient for us to remember that the Salaf fled from Fitan- not mixing, sitting and debating with them (i.e. the people of fitan). And even amongst them, such as the likes of Ayyoub As-Sakhtiyaanee and ibn Seereen did not use to listen to the speech of those (people of bidah). And when Ibn Seereen was asked: “Why do you not speak; why do you not listen to them?” He said: “Indeed, my heart is not in my hands! I am not in control of my heart; I fear for myself that I may be misguided.”
So the likes of these Imaams feared fitna and deviation for themselves; but you the miskeen possess bravery to enable you to challenge ahlul bidah….! Many people say: “We sit with ahlul ahwaa and we take (from them); we distinguish between truth and falsehood; we take what is truth and abandon what is falsehood;” whilst he (i.e. the utterer of this speech) is a miskeen who can neither distinguish between truth and falsehood nor is he in control of his heart. How many a young person has been put to trial through this satanic view and thus he (becomes) lowered and reverts back on his heels (into misguidance) and depraved, and Allaah’s Aid is sought. He falls prey in the enclosures of the people of fitan! Therefore it is obligated on a student of knowledge not to (consider) himself safe from ahlul bidah; for indeed he is not more knowledgeable than Ayyoub and Ibn Seereen, nor can he reach their station (in knowledge, piety etc) and those who followed them.
[Source: الذريعة إلى بيان مقاصد كتاب الشريعة…pages 192-193.slightly paraphrased and abridged]