Final answer:
The term 'Ahl al-Kitab' is used in the Holy Quran to collectively refer to Jews, Christians, and Muslims, recognizing their shared monotheistic belief as People of the Book.
Step-by-step explanation:
The phrase used in the Holy Quran to refer to Jews, Christians, and Muslims collectively is Ahl al-Kitab, which means People of the Book. This term recognizes them as monotheists who share a belief in receiving revealed scripture from God. It also highlights the protection afforded to Jews and Christians under Islamic rule, provided they paid taxes and abided by certain regulations. Muslim belief holds that all these faiths, including Islam, are variations of the same Abrahamic faiths, stemming from a common religious tradition that started with the prophet Abraham. The Quran positions itself as the uncorrupted, final revelation in this monotheistic tradition, as believed by Muslims worldwide, who are part of the Ummah, the universal community of Islamic believers.