The Ten Commandments are found in the book of Exodus and the book of Deuteronomy. In Exodus the commandment of the Sabbath begins with the word remember, and in Deuteronomy with the word keep. Said a medieval sage, "Remember it always, wait for its arrival. . . Wait, look forward to it like one who looks forward to meeting a person he loves," Al-Nakawa, Menorat ha-Maor, 3:575, as cited in Heschel, Sabbath, p. 117.