﴿ فَمَا مِنكُم مِّنْ أَحَدٍ عَنْهُ حَٰجِزِينَ ﴾

“and none of you could have saved him!”

and not one of you ahadin is the subject of mā min being extra used to emphasise the negation; minkum is a circumstantial qualifier referring to ahadin could have defended him hājizīna is the predicate of the preceding mā and it is used in the plural because ahad when employed in a negatory context denotes a plural sense; the suffixed pronoun in ‘anhu refers to the Prophet in other words there is none to prevent Us from punishing him.