Mistakenly uttering words of disbelief or out of mockery
16-5-2011 | IslamWeb
Question:
What is the ruling on a person who mocks some aspect of the religion, such as mocking the command to lead an ascetic life and curbing oneself from the luxuries of life, that is stated in some Hadeeths?
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad 
is His slave and Messenger.
Mocking Allaah The Almighty, His Books, His Messengers, His angels, the rulings of His Sharee‘ah (Islamic law), or the Hadeeths (narrations) of His Prophet, sallallaahu ‘alayhi wa sallam, are acts of disbelief. This is the case whether or not it is done out of mockery or seriousness. Allaah The Almighty Says (what means): {And if you ask them, they will surely say, "We were only conversing and playing." Say, "Is it Allaah and His verses and His Messenger that you were mocking?" Make no excuse; you have disbelieved after your belief. If We pardon one faction of you - We will punish another faction because they were criminals.} [Quran 9:65-66]
Mocking the religion is one of the most grave major sins because the person who commits this sin has a diseased heart. He is not satisfied with the religion and disparages it; moreover, he prefers something else rather than the religion of Allaah The Almighty. This is the ruling if the mockery is done in jest and fun in the manner of the hypocrites. However, if someone mocks the religion seriously, he deserves to be described as a disbeliever. We seek refuge with Allaah The Almighty from all these acts.
If this happens because of a slip of the tongue, by mistake, while reporting a speech or under compulsion, it does not result in a sin on the part of its perpetrator. The Prophet, sallallaahu ‘alayhi wa sallam, said that Allaah The Almighty has pardoned the acts done by his Ummah (Muslim nation) owing to making a mistake, out of forgetfulness or under compulsion. [Ibn Maajah and Al-Haakim] Allaah The Almighty Says (what means): {Whoever disbelieves in Allaah after his belief... except for one who is forced [to renounce his religion] while his heart is secure in faith. But those who [willingly] open their breasts to disbelief, upon them is wrath from Allaah, and for them is a great punishment.} [Quran 16: 106].
The Prophet, sallallaahu ‘alayhi wa sallam, also stated that Allaah The Almighty pardons the Muslim for improper words said out of extreme happiness, like the man who was overwhelmed with happiness and said, “O Allaah, You are my slave and I am your lord!” because he was confused out of extreme happiness. [Muslim] Consequently, if the slip of the tongue occurs because of a mistake, forgetfulness, or lack of attention, we hope that there will be no harm. Anyone who does this act should seek the forgiveness of Allaah The Almighty and hasten to repentance.
If a certain person is judged to be a disbeliever, his previous acts become worthless according to the most sound opinion of the scholars. Therefore, if he repents to Allaah The Almighty, he should renew his marriage contract; if he had performed Hajj (pilgrimage), he should perform it again and repeat all its rites. This is because Allaah The Almighty Says (what means): {And it was already revealed to you and to those before you that if you should associate [anything] with Allaah, your work would surely become worthless, and you would surely be among the losers." } [Quran 39:65]
We draw the questioner’s attention to the fact that the statement that includes the order to accustom oneself to an ascetic lifestyle was narrated by At-Tabaraani 
on the authority of ‘Abdullaah ibn Abi Hadrad. A similar report was made by ‘Umar ibn Al-Khattaab 
. [Sharh Ma‘aani Al-Aathaar by At-Tahaawi]
Allaah Knows best.