Are Christians and Jews kaafir according to Islam?

In a Nutshell: The word "kaafir" refers to someone who doesn't believe in God or the main beliefs of Islam. The Christians and Jews are kaafir and there is a consensus of scholarship on the matter. Terminology: Kaafir (unbelievers) The word "kaafir" refers to someone who doesn't believe in God or the main beliefs of Islam ie unbelievers or disbelievers. Christians and Jews are considered "People of the Book," or Ahl al-Kitab, which means they follow monotheistic religions based on divine revelations. They are therefore given a certain level of respect in Islamic tradition. It is important to note that the word "kaafir" isn't generally used in a negative or pejorative way in Islam. It is simply a term used to describe someone who doesn't believe in the main tenets or beliefs of Islam. Muslims are taught to respect the beliefs of others and to have open and understanding conversations with people of different faiths. Scholarly Opinion - Christians and Jews are Kaafirs This understanding has been common by traditional Muslim scholars across the centuries. Some examples are considered below. Qadi Iyad the Maliki jurist in his book al-Shifa states the consensus of athe word "kaafir" refers to someone who doesn't believe in God or the main beliefs of Islam. But Jews and Christians are considered "People of the Book," or Ahl al-Kitab, which means they follow monotheistic religions based on divine revelations. Ahl al-sunnah scholars argue all non-muslims are blasphemers (kaafirs) and that whomever doubts that or even holds off on it or judged their belief as correct is also a blasphemer (kaafir) by consensus. In his book Faysal al-Tafriqah, Imam Ghazali defines kufr as anything that belies what the Prophet Mohammed (saw) came with. Then he says that therefore, Jews and Christian are kaafir (blasphemers) because their beliefs belie what the Prophet (saw) came with. So any non-muslim is a kaafir because they don't hold the belief that the Prophet (saw) came with. In his book "Al-Iqtisad" under the chapter of describing the groups that we must judge as kaafir, he again defines kufr as anything that belies what the Prophet (saw) came with. Then he defines the different level of belying. In the first level he first mentions the belying of the Jews, Christians, Majus and idol worshippers and the rest of the non-Muslims and then says that the fact they are all kuffar is mentioned in the Qur'an and is by consensus (ijma). Imam Nawawi al-Shafi'i in his book "Rawdat Al-Talibin", under the chapter of apostasy (riddah), gave an example of apostasy: "The one who does not make takfir of non-muslims such as Christians, or even had a doubt whether they are kaafir or not, or judged their belief as correct, this person is kaafir even if he claims that he believes in Islam and he showed that he was muslim." Imam al-Buhuti al-Hanbali in his book Daqa'iq Ulin-nuha under the chapter of apostasy (riddah) gave an example of apostasy: "The one who does not make takfir of non-muslims such as the people of the book, or even had a doubt whether they are kaafir or not, or judged their belief as correct, then this person commits apostasy (riddah)." Ibn Hazm in his book Maratib al-Ijma' relates the consensus of Muslim scholars that Jews and Christians are called Kuffar (disbelievers). In his book al-Fasl fil-milal", he narrated the consensus of Muslim scholars that Jews and Christians are kaafir (disbelievers) and that whomever does not deem them as kaafir is a kaafir (disbeliever) by consensus. Imam Al Qurtubi in his book Amal-Mufhim, mentioned that if a person believes in tawhid but he does not believe in the Prophet (saw) then his belief and tawhid will not benefit him and he is kaafir by consensus without any doubt. Ibn Juzay al-Maliki mentioned the consensus that Jews and Christians are kuffar stating in his book al-Qawanin al-Fiqhiyyah: "There is no difference of opinion about the kufr of the one who denies Godhood or oneness of Allah or associates a partner with Allah or who was on Judaism, Christianity, Majus or Sabaeans." This matter is by consensus as mentioned by Al-Qadi al-Iji. "If a disbeliever fell short to look for the truth of Islam or didn't reach the truth after putting his full effort in finding it, then he will not be safe in the hereafter and he will be hellfire eternally." In his famous book al-Mawaqif and with explanation of the al-Sharif al-Jurjani it is mentioned: "Muslims have made a consensus that disbelievers will be in hellfire eternally without having any breaks from torture, whether they have put excessive effort in looking for the truth, they rejected after knowing its the truth or was lazy to find the truth. This fact of them being in hellfire eternally was rejected by a group that was outside of Islam." Imam ibn al-Tilmisani on his explanation of Ma'alim Usul al-Din of al-Razi said: "And among the matters which consensus (Ijma') has been established upon is the kufr of every person who is on a religion other than the religion of Islam such as Jews, Christians, Majus and the Philosophers who denied that the world is created." Shaikh Abdullrahman al-Saqqaf authored a book refuting perennialism and atheism called al-Sayf al-Haadd liqat' al-Ilhaad. He stated that Muslims have a consensus there is no Islam for the person who does not believe in the two shahadas and that whoever has doubt about the kufr of Jews and Christians then he is kaafir by the consensus of scholars including Imam Shafi'i. He also narrated the statement of Imam al-Nawawi mentioned in his Book Rawdat al-Talibin under the chapter of matters that take the person out of Islam. The Shafi'i scholar Imam Tajjuldin Al-Subki in his famous book of Usul al-Fiqh (Jam' al-Jawami) under the chapter of ijtihad said: "There can be only one correct ijtihad in the intellectual matters and the one who reaches to something other than Islam is mistaken and is kaafir." Imam Abu Hayyan al-Andalusi said in his Tafsir: وأجمع المسلمون على تخليد من مات كافراً في النار "Muslims have made consensus that whomever died as a kaafir then he will be in hellfire eternally." Conclusion The word "kaafir" refers to someone who doesn't believe in God or the main beliefs of Islam. The Christians and Jews are kaafir and there is a consensus of scholarship on the matter. Jews and Christians however are considered "People of the Book," or Ahl al-Kitab, which means they follow monotheistic religions based on divine revelations.