 During his time at the Divinity School he studied Hebrew, Biblical Aramaic, Syriac, Arabic, Akkadian and Sumerian.Smith completed his doctoral dissertation on "The History of the Idea of the Day of Yahweh" in 1899.Smith was then singled out for the Department of Semitic Languages by the president of the university and fellow orientalist, William Rainey Harper, with whom a close professional and personal relationship developed as Smith served as Harper's literary secretary and assisted him with the International Critical Commentary on the Minor Prophets (editorship of the second and third volumes of which would fall to Smith after Harper's death).