Chapter 44: 4-6
Reciting Grace after Meals4.It is customary to remove knives from the table or cover them before reciting grace, for a table is likened to an alter. Concerning the alter's [stones, Deuteronomy 27:5] states: "You shall not lift up iron against them." Iron shortens man's life, while the alter prolongs it. It is not proper that something which shortens should be raised against something which prolongs.
The table also prolongs one's life and atones for one's sins through offering hospitality. [Sanhedrin 103b] praises the great power of hospitality, explaining that it causes the Divine Presence to rest in a home.
Nevertheless, in many places the custom is not to cover knives on Sabbaths and festivals. They are covered during the week, because they are manifestations of Esau's power. However, on Sabbaths and festivals, Satan and the forces of evil have no power. [This and other] customs adopted by the Jews have the weight of Torah law.
5. A person is obligated to recite the grace after meals even if he ate only a k'zayis of bread.
6. A person should not recite the grace while standing or while walking, but only while sitting. Even if he was walking about his home while he ate, or was standing or reclining when he had to recite grace, he must sit, in order to concentrate his attention more completely. He should not recline, for this shows arrogance. Rather, he should sit.
One should wear a jacket or cloak and a hat [in addition to a yarmulke], so that one will be impressed by the fear of heaven and have one's concentration roused.*
* {The Shulchon Oruch HoRav 183:6 quotes the Sages of the Kabbalah, who state that, in particular, these practices must be followed in Eretz Yisrael, in deference to the revelation of G-d's presence there.}
One should recite the grace with awe and reverence. One should not perform any other activity while reciting grace.
