Bismillaah Al-Hamdulillaah wa salatu wa salaamu ‘ala rasulullaah , Amma-ba’d…
“…I (Hudhaifah) said: “Will there be any good after that evil?”
He (sallallaahu ‘alayhi wasallam) said, “Yes, but therein will be Da`khan (a hidden evil).
I asked: What will be the evil hidden therein?
He said: (That time will witness the rise of) the people who will adopt ways other than mine and seek guidance other than mine. You will know (their) good points as well as (their) bad points.“
Student Abu ‘Abdis-Salaam (hafidhahullaah) said: “(Meaning) you will see things from them which you will acknowledge and accept, and you will see from them things which you will disapprove of. So we understand from this, ya ‘Ibad-ullaah (oh slaves of Allaah), that just because there comes from a person who is upon dalaala (misguidance) something that agrees with the haqq (truth) it equates to nothing so long as they are upon the guidance other than the guidance of the Prophet (salallaahu ‘alayhi wa sallam).
Because the Prophet (salallaahu ‘alayhi wa sallam) said that, in describing the deficiency of the people who will seek guidance with a guidance of other than the guidance of the Prophet (salallaahu ‘alayhi wa sallam). We will see certain things that we will acknowledge and accept, and we will see certain things that we will deny and reject.” 
Imaam Ibn Qayyim (rahimahullaah Ta’aala) said:
“If bid’ah only consisted of lies, then it would NOT have been accepted and everybody would even hurry to condemn it and refute it. And if it only consisted of Haqq (truth), then it would not have been a Bid’ah, rather, in agreement with the Sunnah. But it (Bid’ah) consists of both truth and lies in which the truth is clothed with lies.
He (Allaah) Ta’aala said:
وَلاَ تَلْبِسُوا الْحَقَّ بِالْبَاطِلِ وَتَكْتُمُوا الْحَقَّ وَأَنْتُمْ تَعْلَمُونَ
And do not mix the truth with falsehood or conceal the truth while you know [it].
(al-Baqarah, ayah 42).”
[as-Sawaa´iq al-Mursalah (3/925)]
Mufaddal ibn Muhalhal – rahimahullaah – said:
“If the heretic (person of bid’ah) started mentioning his bid’ah right at the beginning of the sitting, you would be on your guard and flee from him. But what he does is begin by mentioning hadeeth from the Sunnah, then, he slips his bid’ah in on you. It might then stick to your heart, but when will it leave your heart?” [Ibn Battah, Al-Ibaanah Al-Kubraa, 2:444]
Also, our father Shaikh Rabee’ bin Haadee al-Madkhalee (hafidhahullaah Ta’aala) said:
“Don’t say about a man who opposes the manhaj of the Salaf that he is a ‘Salafee.’ No, don’t say about a man who opposes the manhaj of the Salaf that he is a Salafee.
Don’t say that a man is ‘Salafee’ until you are sure that he is upon the manhaj [of the Salaf]. He is honored by it, and calls to it. He loves and unites based upon it, and hates and separates because of it. This is a Salafee. But someone who claims that he is ‘Salafee,’ and defends Ahlul-Bid’ah, and defends them against Ahlul-Sunnah, this is not a Salafee whatsoever. Whoever he is – Arab or non-Arab, in the East or in the West – because Salafiyyah has special qualities.
Salafiyyah has signs. Salafiyyah has affairs that differentiate its people from others in Walaa` and Baraa`, and ‘Aqeedah and Da’wah, and the stances that they take.” 
Shaikh Muhammad bin Ramzaan Al-Haajiree (hafidhahullaah) said:
“What are the characteristics of the person of the Sunnah?
His ‘aqeedah (belief). His worship. His following [of the Prophet, salallaahu ‘alaihi wa sallam]. His da’wah (his call), his invitation. His character, mannerisms. His transactions, his dealings with the people. This is the person of the Sunnah. His ‘aqeedah is correct, and it’s based upon following the Prophet (salallaahu ‘alaihi wa sallam). His worship is like that of the Prophet (salallaahu ‘alaihi wa sallam). His calling or invitation is likewise (upon the Sunnah of the Prophet, (salallaahu ‘alaihi wa sallam))…” 
Shaikh Ahmad Al-Bazmool (hafidhahullaah) said:
“And from the most important matters, in my view, that the Salafee youths must pay attention to, is that a person should Not be described as a Salafee because he has speech relating to an issue from the issues of Salafeeyah. (Yet at the same instance) we neither know his stance pertaining to other issues of Salafeeyah, nor do we know the methodology that he is upon. And it is possible that some of those who oppose (Salafeeyah) may agree with the Salafees (in certain matters).” 
- Following the Sunnah (taking Allaah’s Messenger (salallaahu ‘alayhi wa sallam) as Imam in ‘Aqeedah, Manhaj, manner of worship, character)
- Warning against bid’ah and its people
- Sticking to the Jama’ah, and not dividing (and not revolting). 
So do not be deceived just because an individual:- knows the conditions of La illaaha il Allaah
– teaches Qur`an, or memorized Qur`an
– teaches hadeeth, or memorized 40 Nawawee
– teaches ‘Aqeedah
– combines the prayers when it rains
– knows the principles of fiqh
– quotes from some of the Salafee scholars
A Kharijee Takfeeri who has memorized the conditions of La illaaha il Allaah is still a Kharijee Takfeeri.
A grave-worshipping Soofee or Deobandi or Barelwee who teaches Qur`an, or memorized Qur`an is still a grave-worshipping Soofee or Deobandi or Barelwee.An Ikhwaanee who revolts against the rulers and calls to democracy and at the same time this revolter teaches hadeeth is still an Ikhwanee who calls to democracy and revolts against the rulers.A Tahreeri or Suroori who gives sadaqah is still a Tahreeri or Suroori.A Qadari who prays with his hands on his chest is still a Qadaree.An Ash’aree or Jahmee or Mu’tazilee who teaches ‘Aqeedah is still an Ash’aree or Jahmee or Mu’tazilee who rejects Attributes of Allaah, so flee from his ‘aqeedah classes! A Tableeghi who belives in Wahdat al-Wujood, and uses miswak is still a Tableeghi who belives in Wahdat al-Wujood. A Raafidee who drinks with his right hand is still a filthy Raafidee.So don’t be deceived, ya ‘Ibadullaah!