Know – o Muslim brother – that Allaah has obligated upon all of the servants to enter into Islaam and to hold fast to it and to warn against whatever opposes it. So Allaah sent His Prophet Muhammad (sallallaahu ‘alayhi wa sallam) to call to that, and He, the Mighty and Majestic, informed that whoever followed him was indeed guided, and whoever resisted him was indeed misguided. So He warned in many statements concerning the causes for apostasy and the types of disbelief. So the scholars (rahimahumullaah) have mentioned in judgement upon the apostate that the Muslim apostates from his Religion due to many types of invalidators that make his blood and his wealth permissible and by that he leaves Islaam. The most dangerous of these emanate from ten invalidators. 
We shall mention them for you in what follows upon a short path to warn you about them and so that you may warn others in hopes of security and well being, along with a small explanation after mentioning them.
First: From the ten invalidators is shirk (associating partners) in the worship of Allaah. Allaah the Exalted says:
“Verily Allaah does not forgive that you associate partners with Him, but He forgives whatever is below that for whoever He wishes.” [Sooratun Nisaa` 3:116]
Allaah the Exalted says:
“Whoever associates partners with Allaah, then Allaah, then Allaah has forbidden Paradise for him and his dwelling be in the Fire and there will be no helpers for the oppressors.” [Sooratul Maa`idah 5:72]
So from that is supplication to the dead and seeking their aid and taking oaths by them and slaughtering for their sake.
Second: Whoever places intermediaries between himself and Allaah, supplicating to them and asking them for intercession and placing his trust upon them, then he has indeed disbelieved by agreement.
Third: Whoever does not disbelieve in the idolaters, or doubts in their disbelief, or believes in the correctness of their religion, then he has disbelieved.
Fourth: Whoever believes that the guidance of other than the Prophet (sallallaahu ‘alayhi wa sallam) is more complete than his Guidance, or that the judgement of other than him is better than his Judgement, such as those who give precedence to the judgement of the tawaagheet  over his Judgement, then he is a disbeliever.
Fifthly: Whoever hates something from what the Messenger (sallallaahu ‘alayhi wa sallam) came with, or the one who acts like that, then he has indeed disbelieved due to the statement of Allaah:
“That is because they disbelieved in what Allaah revealed, so He rendered their deeds worthless.” [Sooratul Muhammad 47:9]
Sixth: Whoever ridicules something from the Religion of the Messenger (sallallaahu ‘alayhi wa sallam), or its reward, or its punishment, he has disbelieved. The proof for this is the statement of Allaah:
“Say: Was it Allaah and His messenger and His Signs that you were mocking? Make no excuse, indeed you have disbelieved after your faith.” [Sooratut Tawbah 9:65-66]
Seventh: Magic, and from it is sarf (detachment)  and ‘itf (affection) . So whoever does this, or is happy with it – he has disbelieved. The proof is the statement of Allaah:
“And they do not teach anyone until they have said: ‘We are a trial so do not disbelieve.'” [Sooratul Baqarah 2:102]
Eighth: Supporting the disbelievers and cooperating with them against the Muslims. The proof for this is the statement of Allaah the Exalted:
“So whoever forms an alliance with them, then verily he is from them. Verily Allaah does not guide an oppressive people.”  [Sooratul Maa`idah 5:51]
Ninth: Whoever believes that some of the people are free to leave from the Law (sharee’ah) of Muhammad (sallallaahu ‘alayhi wa sallam), then he is a disbeliever due to the statement of Allaah the Exalted:
“Whoever seeks a religion other than Islaam, it will never be accepted from him, and in the Hereafter, he will be from the losers.” [Soorah Aali Imraan 3:75]
Tenth: Turning away from the Religion of Allaah without being knowledgeable about it, nor acting upon it. The proof for this is the statement of Allaah:
“And who is more unjust  than one who is reminded  of the statement of his Lord, then he turns away  from them. Verily We will take retribution  from the criminals.” [Sooratus Sajdah 32:22]
So all of these invalidators do not differentiate between the scoffer or the liberal person or the fearful, except that it is deception. All of them are from the greatest danger and most numerous in occurrence. So it is befitting for the Muslim that he is aware of them and fears them for himself.
Whoever believes in the constitutions and laws that the people take as being better than the Law of Islaam, or that the Laws of Islaam cannot be applied in the twentieth century, or that they are a cause for division amongst the Muslims, or that it restricts a persons devotion to his Lord without entering into the matters of the Next Life. Also entering into the fourth category is whoever thinks that the Ruling of Allaah in cutting the hand of the thief or stoning the adulterer is not valid in this age. Also entering into that is whoever believes that it is permissible to rule by other than the Law of Allaah in conduct and punishments or other than them.
We seek refuge in Allaah from that which necessitates His Anger and His Grievous Punishment. May the Prayers and Peace of Allaah be upon the best of His creation, Muhammad and upon his family and his companions.
[By: Imaam ‘Abdullaah Ibn ‘Abdul ‘Azeez Ibn Baaz|Translated by Maaz Qureshi