Divino Afflante Spiritu §14

¹⁴ The Fathers of the Church in their time, especially Augustine, warmly recommended to the Catholic scholar, who undertook the investigation and explanation of the Sacred Scriptures, the study of the ancient languages and recourse to the original texts. However, such was the state of letters in those times, that not many - and these few but imperfectly - knew the Hebrew language. In the middle ages, when Scholastic Theology was at the height of its vigor, the knowledge of even the Greek language had long since become so rare in the West, that even the greatest Doctors of that time, in their exposition of the Sacred Text, had recourse only to the Latin version, known as the Vulgate.