וּמַ֛יִם בִּמְשׂוּרָ֥ה תִשְׁתֶּ֖ה שִׁשִּׁ֣ית הַהִ֑ין מֵעֵ֥ת עַד־עֵ֖ת תִּשְׁתֶּֽה׃
你喝水也要按限量，就是一欣的六分之一；從這時到次日這時，你要喝這分量。
Pirkei Avot
Such is the way [of a life] of Torah: you shall eat bread with salt, and rationed water shall you drink; you shall sleep on the ground, your life will be one of privation, and in Torah shall you labor. If you do this, “Happy shall you be and it shall be good for you” (Psalms 128:2): “Happy shall you be” in this world, “and it shall be good for you” in the world to come.