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Section: Halacha   Category: Tshuvos
Bais Ovi - Covering Plastic Knives By Birchas Hamazon
Before Birchas HaMazon during a weekday meal the Shulchan Aruch says (OC 180:5) that there is a Minhag to cover all knives on the table.  What about a plastic knives?  Must they be covered as well?

Rav Yitzchok Isaac Liebes zt"l in Shu"t Bais Ovi says that the Mishna Brura (11) brings two reasons from the Bais Yosef why knives need to be covered.  One reason is that our table is compared to a Mizbei'ach.  The mizbei'ach lengthens a person's life and iron which is used to shape weapons shortens a persons life. Therefore as soon we finish eating and have no use for the knife, we cover it.  Accordingly a plastic knife does not need to be covered. The second reason is that once a person became so distraught over the Churban when saying U'Vinei Yerushalayim that he grabbed a knife from the table at stabbed himself in the stomach.  Therefore as a precautionary measure we remove all the knives from plain view.  According to this says the Bais Ovi, even plastic knives should be covered.

He brings another reason from the Mekubalim for covering the knives.  The four items on the table during the meal are Sakin (knife), Mayim (water), Oichel (food), Lechem (bread).  The Roshei Teivos spell out the name of the evil malach Sama-el (Samech, Mem, Alef, Lamed).  As soon as we finish eating we hide the Samech (Sakin/Knife) and introduce the letter Kuf for Kos Shel Bracha, a cup of wine for Birchas HaMazon.  The new combination of letters spells out Michoel, the name of the malach of Rachamim.

Disclaimer: We try to convey the Tshuva to the best of our ability. We admit that our understanding may not be accurate. Please also understand that this Tshuva may not be the final word on this topic. One should consult a Rav before drawing any conclusions.