When Rosh Chodesh falls on two days, how is a document dated if written on the first day (the 30th of the previous month)?
Synopsis
When Rosh Chodesh spans two days, a document written on the first day must reflect its ambiguous calendrical status. The Mechaber rules it is dated as Rosh Chodesh (= 30th of the prior month); the Bach offers a reversed formulation.
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