Sale reportedly spent 25 years in Arabia, thus acquiring his knowledge of the Arabic language and customs during this time; but evidence of dates and facts refute this, such notion are dismissed as fictions by which biography have often been encumbered and disgraced. It is known that he trained as a solicitor in his early years but took time off from his legal pursuits (returning as need to this profession). He took the time to apply himself in the study of the eastern and other languages, both ancient and modern. Mr. Dadichi, the king's interpreter, helped Sale in his studies of oriental dialects. Sale was an early members of a society that was established for the encouragement of learning. The society helped finance the cost of publishing for authors. Sale was also a corrector of the Arabic New Testament (1726) issued by the S. P. C. K..
In 1734, the Oriental scholar published the translation of the Qur'an, dedicated to John Lord Carteret. This was an English translation of the Islamic civil code. Sale provided numerous notes and a "Preliminary Discourse" which was manifest with in-depth knowledge of Eastern habits, manners, traditions, and laws. Voltaire bestowed high praise on Sale's version of the Koran. Sale did not, however, place Islam at an equal level with Christianity. He stated,
He assisted in the writing of the Universal History published in London from 1747 to 1768. When the plan of universal history was arranged, Sale was one of those who were selected to carry it into execution. Sale wrote the chapter, "The Introduction, containing the Cosmogony, or Creation of the World". Critics of the time accused Sale of having a view which was hostile to tradition and the Scriptures. They attacked his account of Cosmogony as having a view giving currency to heretical opinions.