Amongst the actions and statements are those on account of which a person exits from Islaam and it is not a condition that he desires to leaves Islaam (qasd), or desires to commit kufr or that he believes in the statement of kufr he uttered.
Ibn Hajr said, "Amongst the Muslims are those who exit the religion without desiring (qasd) to leave the religion and without choosing a religion other than that of Islaam".
Shaikh ul-Islaam Ibn Taymiyyah, "And in essence, whoever says or commits that which is disbelief, kufr, disbelieves on account of it, even if he did not desire (lam yaqsud) to become a disbeliever (by the act), since no one desires disbelief except as Allaah wills."
To illustrate this point, a person may prostrate to an idol and this act in and of itself is kufr that expels from the religion. The ruling of takfir may be made upon a person, provided the preventative barriers to takfir are removed (such as ignorance, faulty ta'weel, compulsion, error). However, it is not a condition that a person "intended to perform kufr" by this act., before he is judged a disbeliever, since the mushriks who worship the dead and make supplication to them, believing that the dead provide for them and protect them, they never "intend to perform kufr" by these acts, rather they consider them to be worship and nearness to Allaah, yet they are the greatest of acts of shirk and apostasy.
To illustrate with another example, a person who mocks and reviles Allaah or the Messenger, it is not required that the person "desired kufr" by his words of mockery or revilement, and neither is it a condition that he "believed (i'taqada) in what he said" before takfir is made of him. Rather, if he said these words deliberately, intending to say these words, desiring to say these words, then that in and of itself is the kufr that expels from the religion. However, there is a difference between "desiring the act" and "desiring kufr". The latter, "desiring kufr" is of no significance and its presence or absence has no bearing on the ruling of takfir (in those cases where the action is major kufr that expels from the religion). However, the former, "having desired the act", meaning that a person wilfully did the act, then this does have a bearing on the ruling of takfir, for this is related to the preventative barriers and required conditions for the performance of takfir, in the sense that it must be verified that this act did not occur out of compulsion, or error and the likes.
Ibn al-Qayyim said, "It has preceded that the one who uttered, when he found his lost camel, "O Allaah, you are my servant and I am your Lord" erred due to extreme joy and he did not disbelieve by these words, even though he uttered pure and clear kufr. This is because he did not intend to say it. And the one who is compelled to utter kufr, has indeed spoken with a word of kufr, but he does not become a disbeliever since he did not desire to utter this word, as opposed to the one who mocks or jests (about Allaah, the Messenger, or the religion). In this case, such an utterance would necessitate disbelief and divorce, even if he was only joking and fooling around, since he desired to utter these words (qaasidun littakallum bil-lafdh). And even if he was just joking, then this would be no excuse for him, as opposed to the case of the one who is compelled, or who erred, or who was forgetful. Such a one is excused..."
Shaikh ul-Islaam Ibn Taymiyyah said, "Whoever uttered with his tongue a word of disbelief without having any need for it, deliberately saying it, knowing that it is an utterance of disbelief, then he becomes a disbeliever through that both inwardly and outwardly, and we do not make it permissible for it to be said, 'It is possible for him to still be a believer inwardly'..."
Shaikh ul-Islaam added to the above, in explanation of the verse in Surah Nahl, "Whoever disbelieved in Allaah after his belief, except him who is compelled and whose heart is at rest with Imaan. However, those who open their breasts to disbelief, on them is wrath from Allaah, and theirs will be a great torment (Nahl 16:106)" - so he said, "And it is known that he did not intend by the disbelief mentioned here, the disbelief that relates to belief (i'tiqaad) of the heart only, because a man cannot be compelled with respect to this (i.e. his heart cannot be forced to hold a particular belief, even though he may be forced to say it with his tongue). And He excepted the one who is compelled (to disbelief) but did not meant the one who uttered (disbelief) and believed in what he said, because he excepted the one who is compelled..."
In other words, only one who utters disbelief under compulsion is excused, as for the one who utters disbelief, then he has disbelieved, irrespective of whether his heart believed in what he said or not, since although a man can be forced to say something with his tongue, he cannot be forced to accept and believe it with his heart, and hence the compulsion being referred to in the verse mentioned above, is the one that is related to the tongue only. Therefore, it is not a condition that when someone utters disbelief, that he also believes in what he uttered for it to be considered disbelief.
1 Fath ul-Baree (12/373)
2 As-Saarim al-Maslool (p.178)
3 NOTE: If a person desired kufr in his heart, then he would become a disbeliever through that, regardless of whether he performed an act of kufr or not.
4 I'laam ul-Muwaqqi'een (3/63)
5 Saarim al-Maslool (p. 524)