CUTTING OPEN A LETTER
SEIF 13 (Cont.)
The Pri Chadash and Sefer Zichronos says a person is Chayiv for the Malacha of ripping when opening a sealed letter. Even though it is destructive, but it is done with a constructive use (i.e. to facilitate reading the letter.) The Chacham Tzvi permits telling a Goy to open it. This is because (1) it is only destructive, which is a rabbinical prohibition, combined with (2) commanding a Goy to do it, which is also a rabbinical prohibition. Therefore it is a double Shvus (rabbinical prohibition) which is permitted in a time of need. He holds that ripping open the envelope is considered a destructive act, though the reading afterwards is constructive. Since the actual ripping does not create anything constructive since it just allows someone to read the enclosed letter.
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