In Majmoo' al-Fataawaa, Shaykh al-Islaam Ibn Taymiyyah discusses various factions amongst the Muslims who innovated and strayed and he makes the observation that a common trait of all of them is that ascribing to the Salaf and adopting their way is not from the slogans and emblems of Ahl al-Bid'ah. This is a significant observation because we see this matter carrying through to our day whereby the factions, parties, sects and groups present in the field of da'wah do not ascribe to the Salaf and resent and dislike ascription to the Salaf for the reason that it is a threat to their particular doctrine or methodology which is derived for the most part from the mind, speech and writings of a single man - instead of being derived from the understanding of the Salaf.
He says (4/154 onwards):
And the Mu'tazilah declare factions from the Sahaabah and Taabi'een as sinners, and they revile many of them with respect to what they narrated of ahaadeeth which oppose their opinions and desires. Rather, they also make takfeer of those from the Salaf and Khalaf who oppose the foundations (usool) which they adoptedd. Hence, they have such revilement upon the Scholars of the Salaf and in their knowledge that is not found for Ahl al-Sunnah wal-Jamaa'ah.
And ascribing to and adopting (intihaal) the madhhaab of the Salaf is not from their slogans, even if they affirm the khilaafah of the four caliphs and venerate those from the Imaams of Islaam and their majority that are not venerated by those (Raafidah and Khawaarij), for they have revilement upon many of them, this is not the place to (elaborate). And al-Nadhdhaam (a Mu'tazili figurehead) has revilement upon the Sahaabah, this is not the place (to elabaorate)....
So the intent here: Is that the well-known general factions (of the Muslims) known to Ahl al-Sunnah wal-Jamaa'ah as being upon bid'ah, they do not ascribe to the Salaf... (فعلم أن شعار أهل البدع هو ترك انتحال اتباع السلف) and so it is known that the slogan (shi'aar) of Ahl al-Bid'ah is to abandon ascription to following the Salaf. For this reason Imaam Ahmad said in his risaalah to Abdoos bin Maalik, "The founndational principles of the Sunnah with us are: To hold fast to what the Companions of the Prophet (sallallaahu alayhi wasallam) were upon..."
After this Ibn Taymiyyah talks about the Mutakallimeen (Ahl al-Kalaam) such as the Kullaabiyyah, Karraamiyyah and Ash'ariyyah and says that whilst they - in general - do not revile the Salaf and respect and veneration might be found amongst them for the Salaf, they nevertheless do not ascribe to the Salaf. He said (p. 156):
أما أن يكون انتحال السلف من شعائر أهل البدع : فهذا باطل قطعا . فإن ذلك غير ممكن إلا حيث يكثر الجهل ويقل العلم .يوضح ذلك : أن كثيرا من أصحاب أبي محمد من أتباع أبي الحسن الأشعري يصرحون بمخالفة السلف - في مثل مسألة الإيمان . ومسألة تأويل الآيات والأحاديث
As for ascribing to the Salaf being a slogan of Ahl al-Bid'ah, then this is falsehood (baatil) absolutely, for that is not possible, except where ignorance becomes widespread and knowledge diminishes. And what explains this is (the following): that many of the associates of Abu Muhammad [al-Juwaynee) from the followers Abu al-Hasan al-Ash'hari make their opposition to the Salaf explicitly clear in the likes of the issue of faith (eemaan) and the issue of ta'weel of the verses and ahaadeeth (pertaining to the attributes)...
Ibn Taymiyyah goes on to cite statements from their books where they say for example, "The Salaf said such and such but as for the Mutakallimoon from our associates their madhhab is such and such..." so these people explicitly state and acknowledge their opposition to the Salaf, indicating that it is falsehood to claim that they ascribe to the Salaf and adopt their way in principle.
At the end page 156, Ibn Taymiyyah says (after making the previous point):
Does not an intelligent person reflect? Does not the deceived person feel deterred? [By the fact] that [the doctrine of the Salaf] is established from the Salaf even through the explicit acknowledgement of the opposer, yet he invents a new saying that exits (from what they were upon). Is this not an explicit (claim) that the Salaf were astray from Tawheed and Tanzeeh (freeing Allaah of defects) and only the latecomers came to know of it?! This is [known] to be corrupt through necessity of sound knowledge and firm religion.
Whilst many of the groups of innovation may not revile the Salaf (in general as do the Raafidah and the Khawaarij) they do not ascribe to the Salaf in principle, and it is from their slogans not to ascribe to the Salaf. This in turn explains the enmity and hatred and resentment shown by those who are present today of the parties, factions, sects and groups [who are merely inheritors and descendents of those innovations of old] towards those who ascribe to the Salaf and take them and their way as a model of guidance and truth. This explains why many of these parties and groups strive to spread doubts regarding ascription to the Salaf - because it is a direct threat to their doctrine, program and methodology.