Surah Muhammad (47) — Ayah 33

(Ayah 33){ يٰۤاَيُّهَا الَّذِيْنَ اٰمَنُوْۤا اَطِيْعُوا اللّٰهَ وَ اَطِيْعُوا الرَّسُوْلَ … :} That is, the condition for the acceptance of deeds is that a person remains bound to the obedience of Allah and His Messenger. If someone leaves obedience and turns to opposition and starts colluding with the enemies, then all his deeds are nullified, no matter how good he thinks his actions are, just as the hypocrites, who after believing, chose disbelief and after pledging obedience, chose the path of opposition. Here, this is the meaning of the verse, because before and after this, the mention is of the hypocrites. Thus, the meaning of the verse is: "O you who have believed! Obey Allah and obey the Messenger, and do not nullify your deeds like those whose deeds Allah destroyed because of their disbelief, hindering from the way of Allah, and opposing the Messenger." The meaning of the verse is not that if a person commits any disobedience or major sin, then all his previous deeds are nullified, because this is against this verse: «اِنَّ اللّٰهَ لَا يَغْفِرُ اَنْ يُّشْرَكَ بِهٖ وَ يَغْفِرُ مَا دُوْنَ ذٰلِكَ لِمَنْ يَّشَآءُ وَ مَنْ يُّشْرِكْ بِاللّٰهِ فَقَدِ افْتَرٰۤى اِثْمًا عَظِيْمًا » [النساء:۴۸] "Indeed, Allah does not forgive that a partner be associated with Him, but He forgives what is less than that for whom He wills. And whoever associates partners with Allah has certainly fabricated a tremendous sin." Yes, the verse can certainly mean that any deed in which there is no obedience to Allah and His Messenger, and it is not according to their prescribed way, is null and void, because for the acceptance of deeds, sincerity and following the Sunnah are conditions, as Aisha (may Allah be pleased with her) narrated that the Messenger of Allah (peace and blessings be upon him) said: [ مَنْ عَمِلَ عَمَلًا لَيْسَ عَلَيْهِ أَمْرُنَا فَهُوَ رَدٌّ ] [ مسلم، الأقضیۃ، باب نقض الأحکام الباطلۃ و رد محدثات الأمور : ۱۸ /۱۷۱۸ ] "Whoever does an action that is not in accordance with our practice, it is rejected." Some people have deduced from this verse that any voluntary act, whether prayer or fasting or anything else, if started, it becomes obligatory to complete it, because if he leaves it before completion, he has nullified the deed, but this is not correct, nor does it have any connection with the verse. A voluntary act remains voluntary before and after. That which is not obligatory to start is not obligatory to complete. See details in the major sourcebooks.