In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
Shaikh Saaleh Al-Fawzaan [hafidhahullaah] said:
Salafiyyah is to follow the Madhab of the Salafus Saaleh [pious predecessors] – the Sahaabah, the Taa’bi’een and the virtuous generations. Allaah [The Most High] said: [وَٱلسَّـٰبِقُونَ ٱلۡأَوَّلُونَ مِنَ ٱلۡمُهَـٰجِرِينَ وَٱلۡأَنصَارِ وَٱلَّذِينَ ٱتَّبَعُوهُم بِـإِحۡسَـٰنٍ۬ رَّضِىَ ٱللَّهُ عَنۡہُمۡ وَرَضُواْ عَنۡهُ – And the first to embrace Islaam of the Muhaajiroon (those who migrated from Makkah to Al-Madinah) and the Ansaar (the citizens of Al-Madinah who helped and gave aid to the Muhaajiroon) and also those who followed them exactly (in Faith). Allaah is well-pleased with them as they are well-pleased with Him]. [9:100]
And Allaah [The Most High] said about the Sahaabah: [إِنَّ ٱلَّذِينَ ءَامَنُواْ وَهَاجَرُواْ وَجَـٰهَدُواْ بِأَمۡوَٲلِهِمۡ وَأَنفُسِہِمۡ فِى سَبِيلِ ٱللَّهِ وَٱلَّذِينَ ءَاوَواْ وَّنَصَرُوٓاْ أُوْلَـٰٓٮِٕكَ بَعۡضُہُمۡ أَوۡلِيَآءُ بَعۡضٍ۬ۚ – ‘Verily, those who believed, and emigrated and strove hard and fought with their property and their lives in the Cause of Allaah as well as those who gave (them) asylum and help, – these are (all) allies to one another [8:72] – up to His statement- [وَٱلَّذِينَ ءَامَنُواْ مِنۢ بَعۡدُ وَهَاجَرُواْ وَجَـٰهَدُواْ مَعَكُمۡ فَأُوْلَـٰٓٮِٕكَ مِنكُمۡۚ – And those who believed afterwards, and emigrated and strove hard along with you, (in the Cause of Allaah) they are of you]. [8:75 ]
Allaah [Glorified be He and free is He from all Imperfections] said in Surah Al -Hashar:
لِلۡفُقَرَآءِ ٱلۡمُهَـٰجِرِينَ ٱلَّذِينَ أُخۡرِجُواْ مِن دِيَـٰرِهِمۡ وَأَمۡوَٲلِهِمۡ يَبۡتَغُونَ فَضۡلاً۬ مِّنَ ٱللَّهِ وَرِضۡوَٲنً۬ا وَيَنصُرُونَ ٱللَّهَ وَرَسُولَهُ ۥۤۚ أُوْلَـٰٓٮِٕكَ هُمُ ٱلصَّـٰدِقُونَ
وَٱلَّذِينَ تَبَوَّءُو ٱلدَّارَ وَٱلۡإِيمَـٰنَ مِن قَبۡلِهِمۡ يُحِبُّونَ مَنۡ هَاجَرَ إِلَيۡہِمۡ
(And there is also a share in this booty) for the poor emigrants, who were expelled from their homes and their property, seeking Bounties from Allaah and to please Him. And helping Allaah (i.e. helping His religion) and His Messenger (Muhammad). Such are indeed the truthful (to what they say); And those who, before them, had homes (in Al-Madinah) and had adopted the Faith, love those who emigrate to them.” [59:8-9]- up until His [The Most High] statement: [وَٱلَّذِينَ جَآءُو مِنۢ بَعۡدِهِمۡ يَقُولُونَ رَبَّنَا ٱغۡفِرۡ لَنَا وَلِإِخۡوَٲنِنَا ٱلَّذِينَ سَبَقُونَا بِٱلۡإِيمَـٰنِ – And those who came after them say: “Our Lord! Forgive us and our brethren who have preceded us in Faith]. 59:10
The Prophet [sallal-laahu-alayhi-wasallam] said: ”This ummah will split into seventy three sects; all of them will enter the fire except one. They said, ‘which is that (saved sects) O Messenger of Allaah? He (sallal-laahu-alayhi-wasallam) replied: ‘those who are upon that which I and my companions are upon today.” The Prophet [sallal-laahu-alayhi-wasallam] said: ”Adhere to my Sunnah and the Sunnah of the rightly guided Khulafaa after me”
Therefore, salafiyyah is the Methodology that has been obligated on us to follow and we are to abandon all other methodologies that are in opposition to it. The [people of salafiyyah] are the saved sect, Ahlus Sunnah Wal-Jamaa-ah, and they are the aided group till the Day of Judgement. May Allaah include us amongst them.
However, ascription to this methodology [of the Salaf] requires [an acquisition of] knowledge of its fundamentals in order that the Muslim may adhere to it. [One is] required to have knowledge of the other methodologies that are in opposition to Salafiyyah in order to avoid them. Therefore, Salafiyyah upon the path of the pious predecessors has to be [followed] upon knowledge and clear sightedness. It is not enough for the person to ascribe himself to [salafiyyah] whilst being ignorant of it or being in opposition to it. For that reason Allaah [The Most High] said:[ وَٱلَّذِينَ ٱتَّبَعُوهُم بِـإِحۡسَـٰنٍ۬ – And also those who followed them exactly (in Faith)].
They follow [them] with knowledge- they neither fall into extremism nor negligence. They neither exaggerate nor fail to give the affair its right- like those who ascribe themselves to the madhabs of the four imams [Abu Haneefah, Maalik, Shaa-fi’ee and Ahmad] whilst being in opposition to them in Aqeedah and Ibaadaat. And like the one who ascribes himself to the methodology of the Salaf, yet he either declares the Muslims to be disbelievers or rebels against the Muslim rulers, or he follows other directions towards extremism. This person is not a Salafi, rather he is named a khaariji or a Mutazili. Or like the one who ascribes himself to the methodology of the salaf, but speaks with the statement of the Mur’ji’a in the affair of Eemaan and Kufr. This is not salafiyyah.
Therefore, it is obligatory to pay attention to this affair and not to mix the Salafi methodology with the other methodologies that are in opposition to it, and then say: ”all these methodologies [including the salafi methodology] are not from Islaam.” This is recklessness in speech, an oppressive judgement and deception against the people.
[Source: An Excerpt from Al-Bayaan Li-Akh’taa’I Ba’dil Kuttaab. Vol 2 page:173-174. slightly paraphrased]