[3] He is known for, presenting through his books, manuscript evidence supporting alternate views on the origins of Christian and Islamic religious texts.
[9] Torrey held[10] that "in the Koran itself there is no clear evidence that Mohammed had ever received instruction from a Christian teacher, while many facts testify emphatically to the contrary; and [...] on the other hand, the evidence that he gained his Christian material either from Jews in Mekka, or from what was well known and handed about in the Arabian cities, is clear, consistent, and convincing."
These opinions are still debated and, while Torrey's works have definitely weighed on scientific knowledge, scholarship still has not reached a united conviction on these topics.
However, Torrey's arguments[11] on the fact that reading and writing were much more common in the Hijaz that usually thought are confirmed by archaeology of the region in the 20th and 21st centuries, where thousands of inscriptions in Safaitic, Arabic and Nabateo-Arabic were found.
Some of Torrey's studies are included in The Origins of The Koran: Classic Essays on Islam’s Holy Book, edited by Ibn Warraq.