In The Name of Allaah, The Most Merciful, The Bestower of Mercy
Imaam Muhammad Bin Abdul Wahhaab [rahimahullaah] said: ‘’They [People of the pre-Islamic era of ignorance] claimed to follow [their Salaf – pious predecessors], while they clearly opposed and contradicted them.
Shaikh Saaleh al Fawzaan [may Allaah preserve him] commented on the above statement saying:
The common [people] amongst the Jews and the Christians and the people of misguidance amongst those who attribute themselves to Islaam– all of them claim to follow the believers who preceded them. So the Jews claim that they follow Moosaa [alyahis-salaam] and those who believed in him; the Christians claim that they follow the Messiah [alayhis-salaam] and those who believed in him; the people of misguidance of this Ummah claim that they follow the pious predecessors of this Ummah- the Sahaabah, the Taa’bi’een and the At’baa At-Taabi’een- and that what they are upon is the way of the pious predecessors. The claim of everyone who claims to be upon the path of the pious predecessors or upon the methodology of the pious predecessors cannot be sound, until he makes apparent what he is upon based on the Methodology of the pious predecessors. So if that conforms to [the Methodology of the pious predecessors], then he is upon the Methodology of the pious predecessors, and if it is in opposition, then he is not upon the Methodology of the pious predecessors, even if he makes that claim.
Every deviated party [or sect] at present claims to be upon the way of the pious predecessors, but they are not upon the Methodology of the pious predecessors- because the statement of the Prophet [sallal-laahu-alayhi-wasallam] regarding the way of the pious predecessors is: ‘’those upon that which I [Muhamad] and my companions are upon’’ is not applicable to them. This is what it [means] to be upon the methodology of the pious predecessors. As for the one who is in opposition to this, then he is not upon the methodology of the pious predecessors even if he claims that. Those who claim Salafiyyah are many, but they must make apparent what they are upon and if that is in conformity [with Salafiyyah], then it is truth; but if in opposition, then they are not upon the Methodology of the pious predecessors.
Likewise, there are those who attribute themselves to the Madhabs of the Four Imaams whilst being in opposition to the Imaams in Aqeedah, so their ascription is not correct because they oppose [the Imaams] in the most important of affairs and that is the Aqeedah.
[Sharh- Ma’saa’ilil Jaahiliyyah of Sheikh Fawzaan (Page: 295-296). Abridged and slightly paraphrased]