The Gemara discusses the second of Ezra’s ordinances: And that they should read the Torah on every Monday and Thursday. The Gemara asks: Was it Ezra who institute this practice? It was instituted from the beginning, i.e., long before his time. As it is taught: “And Moses led Israel onward from the Red Sea, and they went out into the wilderness of Shur; and they went three days in the wilderness, and found no water” (Exodus 15:22). Those who interpret verses metaphorically said that water here is referring to nothing other than Torah, as it is stated metaphorically, concerning those who desire wisdom: “Ho, everyone who thirsts, come for water” (Isaiah 55:1).