“It is not for a believer, man or woman, when Allaah and His Messenger have decreed a matter that they should have any option in their decision. And whoever disobeys Allaah and His Messenger, he has indeed strayed into a plain error” [al-Ahzaab 33:36]
Shaykh ‘Abd al-Rahmaan al-Sa’di (rahimahullaah) said:
“It is not for a believer, man or woman” means: it is not appropriate or befitting for the one who is described as a believer to do anything other than to hasten to please Allaah and His Messenger, and to flee from incurring the wrath of Allaah and His Messenger, and to obey their commands, and to avoid that which they have prohibited. It is not appropriate for a believing man or a believing woman “when Allaah and His Messenger have decreed a matter” and enjoined it, “that they should have any option in their decision”. They do not have the choice of whether to do it or not, rather the believing man and the believing woman know that the Messenger is dearer to them then their own selves, so they should not let their own whims and desires form a barrier between them and obeying the command of Allaah and His Messenger.
“And whoever disobeys Allaah and His Messenger, he has indeed strayed into a plain error” means, an obvious error, because he has forsaken the Straight Path which leads to the reward of Allaah, and has strayed to another path which leads to a painful torment. So Allaah mentions first the reason for not going against the command of Allaah and His Messenger, which is faith, then He mentions the deterrent for that, which is fear of going astray, which leads to punishment and humiliation. End quote.