While in prison, al-Hudaybi is said to have completed the manuscript for ''Du'at la Qudat'', which was published in 1977, after his death.
Emmanuel Sivan and
Gilles Kepel have argued that the text is a refutation of
Sayyid Qutb's Islamist manifesto ''
Ma'alim fi al-Tariq (Milestones Along the Way). Although Du'at la Qudat'' does not mention Qutb by name and only criticizes Pakistani Islamist
Abul A'la Maududi, it argues against
takfir – the practice of declaring another Muslim a non-believer – that Qutb employed. Scholar Barbara Zollner suggests that Qutb is not a direct target of the text, but rather that al-Hudaybi wanted to respond to a radical marginal group of the Brotherhood. One of the main objectives of the text is to define Muslims and
kafirs, or unbelievers. Qutb had previously argued that so-called Muslim governments were actually non-Islamic
jahiliyyah that must be abolished by "physical power and
Jihad." According to al-Hudaybi, however, the committing of a sin that requires punishment does not make the sinner an apostate. Judgement over Muslims should be left to God alone. Al-Hudaybi disagrees with Qutb, believing that
Shahada, or profession of the belief in Islam alone is sufficient to be a Muslim. == Death ==