Abbas - Tanwîr al-Miqbâs min Tafsîr Ibn ‘Abbâs
(That) torment (is because they have chosen the life of the world) they preferred this worldly life (rather than the Hereafter) and chose disbelief instead of faith, (and because Allah guideth not) to His religion nor save them from His torment (the disbelieving folk) who do not deserve it.
That, threat [of chastisement] for them, is because they have preferred the life of this world, they have chosen it [in preference], to the Hereafter, and because God does not guide the disbelieving folk.
That, opening up of the breast to unbelief and contentment with it, is because they have preferred the life of this world to the Hereafter, since it constitutes the limit and ultimate extent of their knowledge and their knowledge does not extend to the Hereafter because the insights of their hearts are blocked and their preparedness corresponds to the dark lower matters such as corporeal substrata and so they have come to love what they can sense and this suits their state, even though the love of this world is the source of every sin as that [love] necessitates the thick veil behind which and in the folds of which lies all sin, and because God does not guide the disbelieving folk, that is, those who are veiled by the thickest veils since it is impossible for them to receive guidance.
Allah's Wrath against the Apostate, except for the One Who is forced into Disbelief
Allah tells us that He is angry with them who willingly disbelieve in Him after clearly believing in Him, who open their hearts to disbelief finding peace in that, because they understood the faith yet they still turned away from it. They will suffer severe punishment in the Hereafter, because they preferred this life to the Hereafter, and they left the faith for the sake of this world and Allah did not guide their hearts and help them to stand firm in the true religion. He put a seal on their hearts so that they would not be able to understand what is beneficial for them, and He sealed their ears and eyes so that they would not benefit from them. Their faculties did not help them at all, so they are unaware of what is going to happen to them.
(No doubt) means, it is inevitable, and no wonder that those who are like this -
أَنَّهُمْ فِى الاٌّخِرَةِ هُمُ الْخَـسِرونَ
(in the Hereafter, they will be the losers.) meaning, they will lose themselves and their families on the Day of Resurrection.
(except one who was forced while his heart is at peace with the faith) This is an exception in the case of one who utters statements of disbelief and verbally agrees with the Mushrikin because he is forced to do so by the beatings and abuse to which he is subjected, but his heart refuses to accept what he is saying, and he is, in reality, at peace with his faith in Allah and His Messenger. The scholars agreed that if a person is forced into disbelief, it is permissible for him to either go along with them in the interests of self-preservation, or to refuse, as Bilal did when they were inflicting all sorts of torture on him, even placing a huge rock on his chest in the intense heat and telling him to admit others as partners with Allah. He refused, saying, "Alone, Alone.'' And he said, "By Allah, if I knew any word more annoying to you than this, I would say it.'' May Allah be pleased with him. Similarly, when the Liar Musaylimah asked Habib bin Zayd Al-Ansari, "Do you bear witness that Muhammad is the Messenger of Allah'' He said, "Yes.'' Then Musaylimah asked, "Do you bear witness that I am the messenger of Allah'' Habib said, "I do not hear you.'' Musaylimah kept cutting him, piece by piece, but he remained steadfast insisting on his words. It is better and preferable for the Muslim to remain steadfast in his religion, even if that leads to him being killed, as was mentioned by Al-Hafiz Ibn `Asakir in his biography of `Abdullah bin Hudhafah Al-Sahmi, one of the Companions. He said that he was taken prisoner by the Romans, who brought him to their king. The king said, "Become a Christian, and I will give you a share of my kingdom and my daughter in marriage.'' `Abdullah said: "If you were to give me all that you possess and all that Arabs possess to make me give up the religion of Muhammad even for an instant, I would not do it.'' The king said, "Then I will kill you.'' `Abdullah said, "It is up to you.'' The king gave orders that he should be crucified, and commanded his archers to shoot near his hands and feet while ordering him to become a Christian, but he still refused. Then the king gave orders that he should be brought down, and that a big vessel made of copper be brought and heated up. Then, while `Abdullah was watching, one of the Muslim prisoners was brought out and thrown into it, until all that was left of him was scorched bones. The king ordered him to become a Christian, but he still refused. Then he ordered that `Abdullah be thrown into the vessel, and he was brought back to the pulley to be thrown in. `Abdullah wept, and the king hoped that he would respond to him, so he called him, but `Abdullah said, "I only weep because I have only one soul with which to be thrown into this vessel at this moment for the sake of Allah; I wish that I had as many souls as there are hairs on my body with which I could undergo this torture for the sake of Allah.'' According to some reports, the king imprisoned him and deprived him of food and drink for several days, then he sent him wine and pork, and he did not come near them. Then the king called him and asked him, "What stopped you from eating'' `Abdullah said, "It is permissible for me under these circumstances, but I did not want to give you the opportunity to gloat.'' The king said to him, "Kiss my head and I will let you go.'' `Abdullah said, "And will you release all the Muslim prisoners with me'' The king said, "Yes.'' So `Abdullah kissed his head and he released him and all the other Muslim prisoners he was holding. When he came back, `Umar bin Al-Khattab said, "Every Muslim should kiss the head of `Abdullah bin Hudhafah, and I will be the first to do so.'' And he stood up and kissed his head. May Allah be pleased with them both.
Maududi - Sayyid Abul Ala Maududi - Tafhim al-Qur'an
This verse deals with the case of those Muslims who were being persecuted with cruelty and were being-subjected to unbearable torments to force them to give up their Faith. They are being told that if at any time they are forced to utter words of disbelief to save their lives, when in fact in their hearts they are secure against disbelief, they will be pardoned. On the other hand, if they accepted unbelief from the core of their hearts, they shall not escape the torment of Allah even if they succeed in saving their lives.
It does not, however, mean that one should utter words of disbelief to save one's life. This is merely a permission but not the ideal thing for a Believer. According to this permission if one utters such a thing, he shall not be taken to account. In fact, the ideal for a Believer is to utter words of truth in any case whether his body is cut into pieces. There are instances which show that during the period of the Holy Prophet some acted upon the ideal while others took advantage of the permission. There was Khabbab bin Art (May Allah be pleased with him) who was made to lie on embers of fire until the fire was extinguished by the melting of his fat, but he remained firm in his Faith. Then there was Bilal Habashi (May Allah be pleased with him) who was made to put on an armor and stand in the scorching heat. Then he was dragged on the burning sand but he went on saying, "Allah is one." There was another Believer, Habib Gin Zaid bin `Asim, whose limbs were cut one by one by the order of Musailimah, the Liar. Each time his limb was severed it was demanded of him that he should acknowledge the Liar as a prophet but each time he refused to bear witness to his claim of prophethood until he breathed his last. On the other hand, there was the instance of Ammar bin Yasir (May Allah be pleased with him) whose parents were mercilessly butchered before his eyes. After this he himself was put to such unbearable torture that, in order to save his life, he had to utter the same words of unbelief that were demanded of him. Afterwards when he came crying to the Holy Prophet, he said, "O Messenger of Allah, they did not let me go until I spoke evil of you and praised their deities". The Holy Prophet asked him, "How do you feel about this, in your heart?" He replied humbly, "My heart is fully convinced of the Faith." At this the Holy Prophet replied, "If they put you to the same torture again, you may utter the same words".
These words apply to those people who gave up their Faith, when they felt that they could not bear hardships of the Right Way and so they again joined their unbelieving, mushrik people.