Bukhari:
Volume 9, Book 84, Number 60:
Narrated Anas bin Malik:
A Jew passed by Allah's Apostle and said, "As-Samu 'Alaika." Allah's Apostle said in reply, "We 'Alaika." Allah's Apostle then said to his companions, "Do you know what he (the Jew) has said? He said, 'As-Samu 'Alaika.'" They said, "O Allah's Apostle! Shall we kill him?" The Prophet, said, "No. When the people of the Book greet you, say: 'Wa 'Alaikum.'"
Volume 9, Book 84, Number 61:
Narrated 'Aisha:
A group of Jews asked permission to visit the Prophet (and when they were admitted) they said, "As-Samu 'Alaika (Death be upon you)." I said (to them), "But death and the curse of Allah be upon you!" The Prophet said, "O 'Aisha! Allah is kind and lenient and likes that one should be kind and lenient in all matters." I said, "Haven't you heard what they said?" He said, "I said (to them), 'Wa 'Alaikum (and upon you).
Volume 9, Book 84, Number 63:
Narrated 'Abdullah:
As if I am looking at the Prophet while he was speaking about one of the prophets whose people have beaten and wounded him, and he was wiping the blood off his face and saying, "O Lord! Forgive my, people as they do not know."
And there are hadiths where Prophet SM is reported to have said:
"Whoever curses a prophet, kill him"
WHAT TO FOLLOW???
