Al-Mujadila · 58:8

8. O Messenger! Do you not see the Jews who used to secretly whisper when they would see a believer, then Allah prohibited them from such whispering, but they would return to committing exactly that which Allah prohibited them from: secretly discussing sin among themselves i.e. backbiting the believers, inciting people against them, and disobedience to the Messenger. O Messenger! When they come to they greet you with a greeting Allah has not taught you to greet with, i.e. by saying: ‘As-sāmu ‘alayk’ meaning ‘death be upon you’, and they say, rejecting the Prophet (peace be upon him): “Why does Allah not punish us for what we say? Because if he was truthful in his claim that he is a Prophet, Allah would have punished us for what we say about him!” Hell is enough of a punishment for them for what they say; they will definitely suffer its heat. What an evil outcome they will face!