When ‘Abdullaah bin Salaam, may Allah be pleased with him, learnt about the arrival of the Prophet, , in Madeenah, he went to see him and said, “I am going to ask you about three things whose answers are known only to a prophet. What is the first sign of the Hour? What will be the first food to be eaten by the people of Paradise? What decides which parent a baby will take after [in looks]?” The Prophet, , replied:“Jibreel [Gabriel, may Allah exalt his mention] has informed me about this.”Ibn Salaam said,“He [i.e., Jibreel] is the enemy Angel of the Jews.” The Prophet,, said:“As for the first sign of the Hour, it will be a fire that will drive the people from the East to the West. The first food to be eaten by the people of Paradise will be the caudate [extra] lobe of the whale-liver. As for the child’s resemblance to either parents, if the man ejaculates before the woman does, (this results in genetic dominance of the man’s genes over the woman’s) and thus the baby will take after the father; if the woman ejaculates first, the baby will take after his mother.”
Upon this, ‘Abdullaah bin Salaam said,“I testify that you are the Messenger of Allah!”He added, “O Messenger of Allah, the Jews invent lies that would astonish you, so ask them about me before they know about my conversion to Islam.”
The Jews then came, and the Prophet, , said:“What kind of man is ‘Abdullaah bin Salaam among you?”They replied,“The most knowledgeable of us and the son of the most knowledgeable of us and the best of us, and the son of the best of us.”The Prophet, , asked:“What would you think if ‘Abdullaah bin Salaam should embrace Islam?”They replied,“May Allah forbid him from that.”Thereupon, ‘Abdullaah came out to them and said,“I testify that none is truly worthy of worship but Allah, and that Muhammad is the Messenger of Allah!”The Jews then said,“He is the most wicked one of us and the son of the most wicked one of us,”and continued to condemn him. [Al-Bukhari]
They would harm their rabbis who converted to Islam, raise doubts about them, and slander them. The Quran tells us about their guile and defends those believers who were subject to unjust smear campaigns that were launched by the Jews. Allah The Almighty Says (what means): {They are not [all] the same; among the People of the Book is a community standing [in obedience], reciting the verses of Allah during periods of the night and prostrating [in prayer]. They believe in Allah and the Last Day, and they enjoin what is right and forbid what is wrong and hasten to good deeds. And those are among the righteous. And whatever good they do - never will it be removed from them. And Allah is Knowing of the righteous.}[Quran 3:113-115]
Al-Waahidi said in his book Asbaab An-Nuzool,
Ibn ‘Abbaas, may Allah be pleased with him, and Muqaatil said, “When ‘Abdullaah bin Salaam, Tha‘labah bin As‘ad, Usayd bin Sa‘yah, Asad bin ‘Ubayd and other Jews converted to Islam, the rabbis of the Jews said, ‘Only the worst people among us believed in Muhammad. If they were the best of us, they would not have abandoned the religion of their ancestors.’ They also said to them, ‘You betrayed us when you replaced your religion with another religion.’ Consequently, Allah The Almighty revealed (what means): {They are not [all] the same.}[Quran 3:113]”