Shaykh Ibraheem Ar Ruhaylee said: It is imperative though, not to confuse the Ulamaa of Ahlus Sunnah and how their mistakes should be dealt with the clarification of which has already preceded with the Ulamaa of Ahlul Bid’ah, those whom it is obligatory for us to separate from,boycott and warn against.

This is due to the fact that the mistakes of the Ulamaa from Ahlus Sunnah are based upon their diligence in seeking the truth coupled with following the correct methodology and etiquettes when is comes to textual deductions, contrary to the mistakes of Ahlul Bid’ah which are founded upon and the result of following their desires and abandoning the correct methodology and the proper etiquettes as it relates to textual deductions and extractions.  The distinction between the two has to be defined.

This is the sole contrast between Ahlus Sunnah and Ahlul Bid’ah, and by this, it will become clear to the intelligent person, why some of the Imams from Ahlus Sunnah who have erred by agreeing with some of the opinions of the People of Bid’ah in a few specific issues, were not considered to be innovators.

taken from his tremendous book: “Advice to Ahl Sunnah”

Al-Sheikh Al-‘Allamah ‘Abdul-Muhsin Al-‘Abbad hafithahu Allah explains:

The ‘Aalim who is from Ahl Al-Sunnah who commits a Bid’ah in ‘Aqidah is not dealt with in the same way as the people of innovations like the Khawarij, the Rafidah, the Qadariyyah, etc. are dealt with, and: This ‘Aalim is to be excused, his knowledge benefited from, he is to be supplicated for, and he is not to be followed in his mistake, walhamdulillah

Question: We hope for the meaning of the words of Al-Shatibi rahimahu Allah in Al-Muwafaqat to be clarified, where he said: It is necessary to not specify he who committed an innovation in the Din, [an innovation] less than the great innovation like the Khawarij, and this is to maintain the unity and rapport and affection between the general Muslimin

Answer: These words relate to the ‘Aalim if he made a mistake and he had something of an innovation, [in such a case] he is not dealt with the way the people of innovations are dealt with, they who have nothing to do with Ahl Al-Sunnah Wal-Jama’ah, and are in opposition to Ahl Al-Sunnah Wal-Jama’ah. Meaning: That he who committed something of this is to be excused, so he is not declared an innovator, nor is what he has of the Truth abandoned because of what he committed of a mistake

And how many are the ‘Ulamaa of the Muslims whose knowledge the ‘Ulamaa and students cannot do without, and yet they committed something of an innovation, so if they were to be dealt with the way the people of innovations are dealt with; nothing of what they came with and what they had of knowledge would be relied on. And what is known is that of the ‘Ulamaa is he who is from Ahl Al-Hadith and he has matters that relate to ‘Aqidah which are reprehensible, as if he has something mixed (i.e. of his ‘Aqidah), and it could be that he has been put to trial by some of his Mashayikh, and the harm and trial of the student is usually from his Shuyukh if they were deviated

So he who is from Ahl Al-‘Ilm (the people of knowledge) with the Sunnah and he committed something of a mistake in ‘Aqidah or other than ‘Aqidah [then] he is not dealt with the way the people of innovations like the Qadariyyah and the Mu’tazilah, and the Rafidah and the Khawarij are dealt with, rather his knowledge is benefited from and he is supplicated for, and he is not followed in his mistake

From the explanation of the Sheikh ‘Abdul-Muhsin Al-‘Abbad hafithahu Allah of Al-Arba’in Al-Nawawiyyah. (See http://audio.islamweb.net/AUDIO/Fulltxt.php?audioid=170654)