[2] In 1987, completed his dissertation, which dealt with linguistic aspects of the Qere and Kethiv in the Masoretic Text of Scripture.
[3] Cohen continued his work on the Qere and Kethiv in the 1990s, and received the Nehemya Allony Prize in 1998,[4] to fund this project.
[5] In 2007, he published the results of his research: The Kethib and Qere in the Biblical Text: A Linguistic Analysis of the Various Traditions Based on the Manuscript 'Keter Aram Tsova' (Hebrew), The Hebrew University Magnes Press, Jerusalem.
In this book, Cohen sets out to answer the following questions:[6] After four chapters, on orthography, morphology (and morpho-phonology), syntax (and morpho-syntax), and lexicon and style, Cohen presents his conclusion:[7] the vast majority of occurrences of Qere and Kethiv in Scripture reflect different dialects of the ancient Hebrew language (whether earlier and later, or simultaneous).
Because of this, he writes in the preface[8] that this book will be interesting not only to people who are concerned with the phenomenon of Qere/Kethiv, and not even only for people who study Biblical orthography, but to linguists of Hebrew in general, and scholars of the Bible in general.