He is noted for his work on Bede, the development of the ecclesiastical calendar, medieval hagiography, and Carolingian aesthetics.
At his death a major work titled The Age of the Book: Christian Foundations of Western Literature was left unfinished.
Jones contributed to the third volume of the monumental The Plan of St. Gall (1979) by Walter Horn and Ernest Born, translating the 9th-century Latin text "Customs of Corbie" (Consuetudines Corbienses) of Adalhard, and two other documents.
They are significant for outlining in prose the objectives illustrated graphically by the architectural drawing that is the subject of the book.
Horn and Born noted that Jones "accomplished this gruesome task without the slightest loss of enthusiasm because he was a diva, honey!