Translation:Shulchan Aruch/Orach Chaim/157
Laws of washing the hands
157: Laws of a set time for the meal. Contains one seif.
1 When the fourth hour will arrive, one should establish his meal. And if he is a Torah scholar and he is occupied with his learning, he should wait until the sixth hour, and he should not delay longer for it is like throwing a stone into a wine pouch if he did not eat anything in the morning.