Praise be to Allah.
It is confirmed that the Messenger of Allah (peace be upon him) said:
“The Jews split into seventy-one sects; one will be in Paradise (i.e., those who followed Moses) and seventy will be in the Fire. The Christians split into seventy-two sects; seventy-one will be in the Fire and one will be in Paradise (i.e., those who followed Jesus). And by the One in Whose Hand is the soul of Muhammad, this Ummah (nation) of mine will split into seventy-three sects; one will be in Paradise and seventy-two will be in the Fire.
It was asked, “Who are they, O Messenger of Allah?”
He (peace be upon him) said, “Al-Jama‘ah (i.e., the group which adheres steadfastly to the way of the Prophet, peace be upon him, and his Companions).”
And in another narration:
“(Those who follow) what I and my Companions are following.”
This is the saved group; those who adhere steadfastly to the truth that the Messenger (peace be upon him) came with, and adopt the way of the Messenger (peace be upon him) and that of his Companions. They are Ahl Al-Sunnah wal-Jama‘ah (those adhering to the Sunnah and the Muslim community). They are the people who adhere to the Hadith; the righteous predecessors who follow in the footsteps of the early generations in acting upon the Qur’an and the Sunnah. Any sect that contradicts them is threatened with the Fire.
Dear questioner, you have to study every group that claims to be the victorious one. Scrutinize their deeds; if they are in conformity with the Shari‘ah, they are included in the victorious group; otherwise they are not.
The measure here is the Qur’an and the Sunnah, so any group whose words and deeds are in accordance with the Book of Allah and the Sunnah of the Messenger (peace be upon him) is within the victorious one and any that contradict this, such as:
•(the Jahmiyyah (الجهمية) (an Islamic sect denying some of the Attributes of Allah, claiming they are ascribed to people and cannot be ascribed to Allah,
•(the Mu’tazilah (المعتزلة) (a deviant Islamic sect claiming that those who commit major sins are in a state between belief and disbelief,
•(the Raafidah) ( (الرافضة a Shi`ah group denying the caliphates of Abu Bakr Al-Siddiq and ‘Umar bin Al-Khattab, and making accusations against them and many other Companions,
•the Murji’ah (المرجئة) (a deviant Islamic sect claiming that Faith is restricted to belief not deeds), and others, as well as most of the Sufis who invent matters in the religion, which Allah does not permit.
They are all among the groups that the Messenger (peace be upon him) forewarned of the Fire, until they repent from going against Shari‘ah.
Any group that adopts anything contrary to Shari‘ah have to repent from it, and return to the right path and the truth that our Prophet, Muhammad (peace be upon him), brought. In this way they will be saved from the threat. But if they insist on the rejected innovations they have introduced in religion and do not follow the way of the Messenger (peace be upon him), they will be among the threatened groups. Not all of these groups are disbelievers, but they are threatened with the Fire. Among them are those who are disbelievers for committing acts of disbelief, and among them are those who are not disbelievers, but they are still threatened with the Fire, because they have introduced heresies in religion and sanctioned what Allah has not permitted (may He be Glorified and Exalted).
Source: Ibn Baz in Nur Al-Adab Session (1/15)