Danger of Taking Knowledge From Deviants

For those who still use the hadith of Abu Hurayrah رضي الله as justification for taking knowledge from anywhere without minding 'aqeedah and good conduct, it should be understood that the hadith is not an evidence for taking knowledge from just anyone. It only meant that a liar can say the truth sometimes. But the fact that he sometimes says the truth doesn't mean we should look up to him or rely on him for knowledge. The worst people to take knowledge from are those who mix the truth with falsehood, and a lot of people are like this within the fold of Muslim ummah today. They mix the truth with falsehood just to get people confused about their true nature. But it is clear that people who mix truth with falsehood are to be distanced from. They are the people of innovation and desire. They mix the truth with falsehood so that the truth could be hidden. Allaah says: 

(وَلَا تَلْبِسُوا الْحَقَّ بِالْبَاطِلِ وَتَكْتُمُوا الْحَقَّ وَأَنْتُمْ تَعْلَمُونَ)

And do not mix the truth with falsehood or conceal the truth while you know [it] [Surat Al-Baqarah 42, Sahih International]

Firstly, Abu Hurayrah رضي الله عنه didn't take Shaytaan as a teacher. The Prophet صلى الله عليه وسلم was his teacher and he confirmed what Shaytaan told him from the Prophet صلى الله عليه وسلم who happened to be his teacher. The Prophet صلى الله عليه وسلم as reported in the hadith said, "Indeed he told you the truth, although he is an inveterate liar". 

Two, if Abu Hurayrah رضي الله عنه had knew it was Shaytaan in the first place, would he have given him audience at all, talkmore of believing what he said? 

Therefore, if it is said that an innovator says something or one stumbles upon a statement of an innovator that is in accordance with the Qu'ran and Sunnah, no problem, one would take it because of his proofs that aligns with the sunnah. But to make him a favorite teacher or mentor, one can't and one shouldn't. 

In the explanation of Sheikh Rabee' حفظه الله in Sharh Usul Sunnah, he mentioned that one of the salaf said: he would not even allow an innovator to recite a single verse or hadith to him because he is not in control of his heart. That is what Imam Al-Bukhari and other hadith reporters رحمهم الله did that gave their works credence. If they knew someone had one deviation or the other, especially in 'aqeedah, they used not to take any hadith from him. 

This is not to say that those we take knowledge from are perfect or infallible. We are only trying to follow the golden advice of Muhammad Ibn Seereen رحمه الله that,

"Knowledge is religion, so watch who you take it from".

Our salaf used not to ignore the speaker and follow the speech as some people try to advocate today. I watched a video of Mufti Menk (may Allaah make him firm upon Sunnah and manhaj salaf) where he emphasised that we can take knowledge from anyone regardless of his creed because all scholars are liable to make mistakes. He said we should "leave the bad and take the good". With due respect, this position is wrong. What we know clearly is that the salaf used to watch who they took knowledge from.

I was able to understand from Imam Ahmad's Usul Sunnah as explained by different scholars that we should watch who we take knowledge from. The salaf used not to take knowledge of the deen from the disbelievers, orientalists and people of innovation. If the personality and 'aqeedah of speakers are to be ignored in the process of seeking knowledge, the science of hadith would have been corrupted. But if an innovator is reported to have said something based on evidence (Quran and Sunnah), we must accept it. 

May Allaah guide us aright.