A notable point concerning commonalities between the Qur’ān and the Bible is the clear influence of the Bible in the development of Islām. Every surah has some allusion or reference to it, so the Qur’ān depends upon the biblical knowledge of its audience. Some of these influences may be seen in Judaism and the perspective of Syrian Nestorian Christianity. Muhammad had contact with a Nestorian monk in Damascus on his caravan expeditions, and in A.D. 631 in Medina with a delegation of sixty Christians from Najran, near Yemen, with whom he made a treaty after a debate. Some qur’ānic stories are a recasting of biblical accounts in new settings as an “identification technique” of placing stories in the reader’s setting, such as Ibrahim and his son Isaac moved from Canaan (Palestine) to Mecca in the Ḥijāz.
There are numerous extra biblical influences upon the development of the Qur’ān. The addition to the biblical account of Ibrahim and Ishāq building the house of God is borrowed from Syrian Jacob of Serugh (451-521), with Islāmic tradition changing the son to Ismā’īl. Another example, Surah 5:32 comes from the Jewish Mishnah (redacted around A.D. 250) which says, “Whoever destroys a single life is considered by Scripture to have destroyed the whole world, and whoever saves a single life is considered by Scripture to have saved the whole world.” The account of Abraham being saved from Nimrod’s fire is scattered in various qur’anic passages and Tradition. It originated in the ancient Jewish book called Midrâsh Rabbâh.
Zoroastrian influence upon the Qur’an came from Salman Farsi from Persia, who was raised “as a Zoroastrian and became a magus scholar in that religion. Becoming disillusioned with his religion, he converted to Catholicism in Syria. Upon traveling from Syria to Arabia he was captured and sold as a slave in Medina. After the hijra to Medina, Muhammad freed him from slavery, he became a Muslim, and they had many conversations through which he became a significant figure in Islam, including suggesting building the ditch for defense of Medina. Many parallels can be made between Muhammad and Zoroaster.
Muslims claim that to rightly interpret the Qur’ān, one must have the Hadith [“news”; Muhammad’s sayings] and Sunnah [traditions and practices]. As Maryam Jameelah explains, “…a proper and detailed understanding of Holy Quran is not possible without some knowledge of the relevant Hadith, for how can the Holy Text correctly be interpreted except by the Prophet to whom it was revealed? Those who disbelieve the Hadith also disbelieve the Qur’ān for its revelation explicitly tells us that one cannot follow what God wants us to do without an unquestioning acceptance of the authority of the Holy Prophet Muhammad (peace and blessings of Allah be upon him).” Thus Tradition as a source of authority for the Muslim is endorsed by the following hadith: Abu Bakr as-Siddiq said, “I will not leave anything Allāh’s Messenger (ﷺ) did, because I am afraid that if I left something from his tradition, then I would go astray.” The Hadith are used to interpret the Qur’ān and provide context as to when and under what circumstances the revelations were given to Muhammad. It is believed that through inner revelation by divine inspiration, Muhammad provided specific application by example to the broad principles found in the Qur’ān. Many allusions to things in the Qur’ān are elaborated upon extensively through generations of the oral development of the Hadith over about 120-290 years. The Hadith grew as new situations were encountered to which new teachers sought to give qur’ānic application. In practice, living by the Hadith and Sunnah of the Prophet takes on a larger role for the average Muslim than the Qur’ān, despite the Qur’ān being the first source of authority.
 See Gabriel Said Reynolds, The Qur’an and the Bible: Text and Commentary (New Haven: Yale University Press, 2018).
 Craig Considine, ‘Pluralism and the Najran Christians: How Prophet Muhammad Went Beyond Tolerance,” Huff Post (02/17/2017); https://www.huffpost.com/entry/pluralism-and-the-najran-christians_b_9235554 (accessed 11/01/2020).
 Miriam Lindgren Hjälm, “The Qurʾānic Subtext of Early Arabic Bible Translations,” Biblia Arabica; https://biblia-arabica.com/the-qur%ca%beanic-subtext-of-early-arabic-bible-translations/ (accessed 5/26/2020).
 Joseph B. Witztum: “The Syriac Milieu of the Quran: The Recasting of Biblical Narratives.” Ph.D. dissertation submitted at Princeton University, 2011, 168.
 “The Origins of the Precept ‘Whoever Saves a Life Saves the World,’” Mosaic (October 31, 2016); //mosaicmagazine.com/observation/2016/10/the-origins-of-the-precept-whoever-saves-a-life-saves-the-world/ (accessed 7/8/2020). Targum of Jonathan ben Uzziah; also, the Targum of Jerusalem.
 Surah 2:260; 6:74-84; 19:42-50; 21:52-72; 26:69-79; 29:15, 16; 37:81-95; 43:25-27; 60:4.
 Qissas al Anbia and Arâish al Majâlis.; Abdul Feda, Ancient History from the Mukhtasar Fi Akhbâr il Bashar.
 “hijra” –after 13 years of preaching in Mecca and suffering persecution from the pagans, Muhammad was invited to become a leader in Medina. He migrated with some of his followers in A.D. 622. This is the year of the start of the Muslim lunar calendar.
 Shayesteh, Daniel. Islam and the Son of God. Sydney, Australia: Talesh Books, 2004, 2010), 15-19.
 Maryam Jameelah, Islam Versus Ahl-Kitab Past and Present (Sant Nagar—Lahore, Pakistan: Mohammad Yusuf Khan, 1968), xxiii-xxiv.
 Sahih al-Bukhari, 3092, 3093.