Originally Posted by Karl
We cannot say they are both
wrong. The Prophet :saws: warned us that there will be splitting in the Ummah, and how to distinguish between the correct path and all the wrong ones.
It was narrated from Mu’aawiyah ibn Abi Sufyaan (may Allaah be pleased with him) that he said: The Messenger of Allaah :saws: stood among us and said: “Those who came before you of the people of the Book split into seventy-two sects, and this ummah will split into seventy-three: seventy-two in Hell and one in Paradise, and that is the Jamaa’ah
(main body of Muslims).” [Narrated by Abu Dawood (4597) and others]
The Prophet :saws: also described them in the following terms: “My ummah will split into seventy-three sects, all of whom will be in Hell except one group.” They said: Who are they, O Messenger of Allaah? He said: “(Those who follow) that which I and my companions follow.”
[see Jami` at-Tirmidhi; Book 40, Hadith 36]
Allaah :swt: decreed that this division should happen when some groups drifted away from the way of the main body of the Muslims and developed their own different approach, and they were distinguished by their own names and character. Those sects are called after the false beliefs that they introduced or the person who founded the sect. You can see that when you examine the names of all the sects.
As for the people of the Sunnah, their attribution is to the Sunnah of the Messenger :saws: which he himself enjoined to be followed. They have no leader they follow unconditionally except the Prophet :saws:. They follow the Qur’an, Sunnah and scholarly consensus. They are followers of the pious predecessors. Their creed became clear and manifest at the sending of the Messenger of Allah :saws:, in contrast to the creeds of the People of Innovation which were given birth after his time - some of them appeared toward the end of the epoch of the Companions and some of them appeared after that.
It is noteworthy to read what the scholars have said regarding the Ahlus-Sunnah:
Imam ash-Shatibi, al-I'tisam [1/79] said, 'Abdur-Rahman bin Mahdi said, "Malik bin Anas was asked about the Sunnah and he replied: It is that which has no other name but this: the Sunnah, then he recited the verse, And this is my Straight Path so follow it and do not follow other paths lest they misguide you from His Path... (6:153)"'
Ibn al-Qayyim, Madarij as-Salikin [3/179] said, 'One of the Imams was asked about the Sunnah to which he replied: It is that which has no other name but the Sunnah, meaning by this that Ahlus-Sunnah have no title to attribute themselves to, save this.'
Ibn 'Abdul-Barr, al-Intiqa' [p. 35] said, 'A man asked Malik about who Ahlus-Sunnah were and he replied: Ahlus-Sunnah are those that have no epithet that would describe them: neither Jahmi nor Qadari nor Rafidi.'
Even the terms such as 'Ahlus-Sunnah', 'Al-Jama'ah', and other similar descriptions can be traced back to the Hadith and sayings of the Companions or the Salaf.
Ibn Taymiyyah :rh: says in his book on orthodox Sunni creed, Al-Aqeedatul Wasitiyyah:
The Path of Ahlu'l-Sunnah
The path of Ahlu'l-Sunnah wa'l-Jama'ah is to follow the footsteps of the Prophet :saws: inwardly and outwardly, it is to follow the way of the forerunners: the Muhajirun and the Ansar, and it is to follow the Prophet's legacy when he said,
'Hold fast to my Sunnah and the sunnah of the Rightly Guided Caliphs after me. Hold fast to it with the molar teeth. Beware of newly invented matters because every innovation is miguidance.' [Ahmad #17142-17155 and Tirmidhi #2676]
They know that the most truthful words are the words of Allaah and that the best guidance is the guidance of Muhammad :saws:. They give preference to the speech of Allaah over the speech of all the different groups of people, and they give precedence to the guidance of Muhammad :saws: over the guidance of everyone else. It is because of this that they are called Ahlu'l-Sunnah. They are called Ahlu'l-Jama'ah because the word Jama'ah here refers to unifying, the opposite of which is splitting. This holds true even though the term Jama'ah has become the actual name of the people themselves who have united together. The third fundament is consensus (ijma') which is relied on in matters concerning knowledge and religion.
They use these three fundaments to judge everything that people do of speech and deeds, both inward and outward, which is connected to the religion. The consensus that can be accurately ascertained is that which the Righteous Salaf were upon for after then, differences increased and the nation spread.
 The author, Majmu' Fatawa, vol.3, pg. 347, said that they were called Ahlu'l-Sunnah because, 'They do not have anyone that they follow, i.e. follow rigidly and unswervingly, save the Messenger of Allaah :saws:. They have the most knowledge of his statements and his conditions. They are the most stringent in discerning the weak from the authentic. Their Imams have deep understanding of them and they fully understand their meanings. They closely follow them in terms of believing them, following them and loving them. They show allegiance to those who show allegiance to (his words and states) and enmity to those who oppose them...'
[Taken from, The Creed of Al-Wasitiyyah, translated by Abu Rumaysah]
So upon studying this, it becomes clear who are the upon the correct way and who have split away from it. We have been directed towards following the Sunnah of the Prophet :saws: and the Sunnah of his Rightly Guided Khalifahs. And sometimes scholars will use terms such as Ahlus-Sunnah in contrast to the shi'a or people of innovation, to clarify what is the way of the Messenger :saws: and to point out the beliefs that oppose it. Let us try to attain and adhere to the qualities of the people of the Sunnah.
I will close this thread now as we already have articles on differences between Sunnis and Shi'as in the section on sects and methodology.
And Allaah :swt: knows best.