1 – Shirk or associating others in worship with Allaah.
Allaah says (interpretation of the meaning):
“Verily, Allaah forgives not (the sin of) setting up partners (in worship) with Him, but He forgives whom He wills, sins other than that, and whoever sets up partners in worship with Allaah, has indeed strayed far away”
“Verily, whosoever sets up partners (in worship) with Allaah, then Allaah has forbidden Paradise to him, and the Fire will be his abode”
That includes praying to the dead, seeking their help, making vows and offering sacrifices to them or to the jinn or to the grave.
2 – Whoever sets up intermediaries between himself and Allaah, asks them to intercede, and puts his trust in them, is a kaafir (disbeliever) according to scholarly consensus.
The evidence for that is the verse in which Allah, may He be exalted, says (interpretation of the meaning):
“And they worship besides Allah things that hurt them not, nor profit them, and they say: ‘These are our intercessors with Allah.’ Say: ‘Do you inform Allah of that which He knows not in the heavens and on the earth?’ Glorified and Exalted be He above all that which they associate as partners with Him!”
Whoever does that is akin to those who worship idols. It doesn’t matter whether the intermediary is Muhammad (salallahu alayhi wasalam), Jesus (Alayhi wasalam), Ali & his sons (Rodiyallahu anhumma), Ahmad Tijani, Ibrahim Niyas, etc.
3 – Whoever does not regard the Mushrikeen (Christians, Jews and other Non-Muslims) as kaafirs, or doubts that they are kaafirs, or regards their way as correct, is a kaafir.
4 – Whoever believes that anything other than the teaching of the Prophet (peace and blessings of Allaah be upon him) is more complete than his teachings, or that the rulings of anyone else are better than his rulings – such as those who prefer the rule of false laws to his rulings – is a kaafir.
5 – Whoever hates any part of that which the Prophet (peace and blessings of Allaah be upon him) brought, even if he acts in accordance with it, is a kaafir, because Allaah says (interpretation of the meaning):
“That is because they hate that which Allaah has sent down (this Qur’aan and Islamic laws); so He has made their deeds fruitless”
6 – Whoever makes fun of anything in the religion of the Prophet (peace and blessings of Allaah be upon him), or makes fun of any texts that refer to rewards or punishments, is a kaafir. The evidence for that is the verse (interpretation of the meaning):
“Say: Was it at Allaah, and His Ayaat (proofs, evidences, verses, lessons, signs, revelations, etc.) and His Messenger that you were mocking?
Make no excuse; you disbelieved after you had believed”
7 – Sihr (witchcraft) – including spells to turn one person against another or to make someone love another. Whoever does this or approves of it is a kaafir. The evidence for that is the verse (interpretation of the meaning):
“but neither of these two (angels) taught anyone (such things) till they had said, ‘We are for trial, so disbelieve not (by learning this magic from us)’”
8 – Supporting the mushrikeen and helping them against the Muslims. [/b]The evidence for that is the verse in which Allaah says (interpretation of the meaning):
“O you who believe! Take not the Jews and the Christians as Awliyaa’ (friends, protectors, helpers), they are but Awliyaa’ of each other. And if any amongst you takes them (as Awliyaa’), then surely, he is one of them. Verily, Allaah guides not those people who are the Zaalimoon (polytheists and wrongdoers and unjust)”
[b]9 – Whoever believes that some people are allowed to operate outside the law of Muhammad (peace and blessings of Allaah be upon him) just as al-Khidr operated outside the law of Moosa (peace be upon him) is a kaafir, because Allaah says (interpretation of the meaning):
“And whoever seeks a religion other than Islam, it will never be accepted of him, and in the Hereafter he will be one of the losers”
[Aal ‘Imraan 3:85]
10 – Turning away from the religion of Allaah, not learning it and not acting in accordance with it. The evidence for that is the verse (interpretation of the meaning):
“And who does more wrong than he who is reminded of the Ayaat (proofs, evidences, verses, lessons, signs, revelations, etc.) of his Lord, then turns aside therefrom? Verily, We shall exact retribution from the Mujrimoon (criminals, disbelievers, polytheists, sinners)”
11. Inventing a lie against Allah (especially forbidding what He permits or permitting what He forbids).
And say not concerning that which your tongues put forth falsely: “This is lawful and this is forbidden,” so as to invent lies against Allah. Verily, those who invent lies against Allah will never prosper.
Say: “Verily, those who invent lie against Allah will never be successful”
A brief enjoyment in this world! – and then unto Us will be their return, then We shall make them taste the severest torment because they used to disbelieve [in Allah, belie His Messengers, deny and challenge His Ayat (proofs, signs, verses, etc.)].
It does not matter whether a person is joking, serious or afraid, unless he is forced to do any of these.
We ask Allaah to help us all to do that which pleases Him, and to guide us and all the Muslims to His Straight Path, for He is All Hearing, Ever-Responsive. May Allaah send blessings and peace upon our Prophet Muhammad and his family and companions.
Originally posted @ https://www.nairaland.com/4752792/summary-things-throw-muslim-out