﴿ فَلَنَسْـَٔلَنَّ ٱلَّذِينَ أُرْسِلَ إِلَيْهِمْ وَلَنَسْـَٔلَنَّ ٱلْمُرْسَلِينَ ﴾

“Thus, [on Judgment Day] We shall most certainly call to account all those unto whom a [divine] message was sent, and We shall most certainly call to account the message-bearers [themselves];”

(Then verily We shall question those unto whom (Our message) hath been sent) with the messengers, i.e. We shall question these people about their response to the messengers, (and verily We shall question the messengers) about their conveyance of the message.