Quran 5:82 says: "Thou wilt find the most vehement of mankind in hostility to those who believe (Muslims) to be the Jews and the idolaters. And thou wilt find the nearest of them in affection to those who believe (Muslims) to be those who say: Lo! We are Christians. That is because there are among them priests and monks, and because they are not arrogant."
The Jews are mentioned very often in the Quran. In fact, they are the most frequently mentioned people in the Quran. They are sharply criticized as murderers of prophets, bringers of mischief, and deceivers. They are described as disgusting, cursed animals. Muhammad himself had very bad experiences with Jews. Among other things, he was betrayed by Jews, he had wars with them, and a Jewish woman poisoned him. The Jews are also mentioned very often in the Hadiths. In a hadith (Sahih al-Bukhari 2926), Mohammed prophesies the annihilation of the Jews by the Muslims. There are more hadiths in which Muhammad speaks negatively about the Jews, for example Sahih Muslim 2869: "Muhammad went out after the sun had set and he heard some sound and said: It is the Jews who are being tormented in their graves."
The sad thing is that shortly after Muhammad's death, the Muslims were very quickly deceived by the Jews. The first major fitna (conflict) was caused by a Jewish man from Yemen named Abd Allah ibn Saba. He founded Shi'ism, which triggered a massive conflict among Muslims. This conflict ultimately led to the assassination of the third caliph, Uthman ibn Affan. This is also the reason why there are certain similarities between Judaism and Shiism that do not exist in Sunnism.
Excerpt from Life of Muhammad:
“The apostle (Muhammad) said, ‘Kill any Jew that falls into your power.’ Thereupon Muhayyisa b. Mas’ud leapt upon Ibn Sunayna, a Jewish merchant with whom they had social and business relations, and killed him. Huwayyisa was not a Muslim at the time though he was the elder brother. When Muhayyisa killed him Huwayyisa began to beat him, saying, ‘You enemy of God, did you kill him when much of the fat on your belly comes from his wealth?’ Muhayyisa answered, ‘Had the one who ordered me to kill him ordered me to kill you I would have cut your head off.’ He said that this was the beginning of Huwayyisa’s acceptance of Islam. The other replied, ‘By God, if Muhammad had ordered you to kill me would you have killed me?’ He said, ‘Yes, by God, had he ordered me to cut off your head I would have done so.’ He exclaimed, ‘By God, a religion which can bring you to this is marvellous!’ and he became a Muslim.”