Calendar Postponement Rules

When the molad of Tishri occurs at a time of the week that is unaffected by the four postponement rules below, the Feast of Trumpets is on the same day as the molad.

Rule 1:

When the molad of Tishri occurs at noon or later (18h 0p), the Feast of Trumpets is postponed until the next day.

Rule 2:

When the molad of Tishri or a postonement occurs on a Sunday, Wednesday or Friday, the Feast of Trumpets is postponed one day, to a Monday, Thursday or Sabbath respectively.

Rule 3:

When the molad of Tishri of a common year occurs on a Tuesday, at or after (3d) 9h 204p, the Feast of Trumpets is postponed to a Wednesday, and by Rule 2, further postponed to a Thursday.

Rule 4:

When the molad of Tishri of a common year immediately following an intercalary year occurs on a Monday after (2d) 15h 589p, the Feast of Trumpets is postponed to a Tuesday.