Selichot (, singular: , səlīḥā) are Jewish penitential poems and prayers, especially those said in the period leading up to the High Holidays, and on fast days. The Thirteen Attributes of Mercy are a central theme throughout these prayers. Selichot of the High Holidays In the Sephardic tradition, recital of Selichot in preparation for the High Holidays begins on the second day of the Hebrew month of Elul. In the Ashkenazic tradition, it begins on the Saturday night before Rosh Hashanah. If, however, the first day of Rosh Hashanah falls on Monday or Tuesday, Selichot are said beginning the Saturday night prior to ensure that Selichot are recited at least four times. This may be because originally the pious would fast for ten days during the season of repentance, and four days before Rosh Hashanah were added to compensate for the four of the Ten days of Repentance on which fasting is forbidden – the two days of Rosh Hashanah, Shabbat Shuvah, and the day preceding Yom Kippur—and, while the fasts have since been abandoned, the Selichot that accompanied them have been retained. Alternatively, the Rosh Hashanah liturgy includes the Biblical phrase, "you shall observe a burnt offering", and like an offering which needs to be scrutinised for defects for four days, so too four days of self-searching are needed before the day of judgment. In the Italian rite, Selichot always begin on a Monday or Thursday shortly before Rosh Hashanah. If Rosh Hashanah falls on Monday, they begin the previous Monday. If Rosh Hashanah falls on a Tuesday, they begin on the Monday eight days before. If Rosh Hashana falls on Thursday, they begin the previous Thursday. If Rosh Hashanah falls on Shabbat, they begin the Monday of that week. Selichot refers to both the poetic piyyutim that compose the service as well as to the service itself. In most modern Sephardic communities, Selichot services are identical each day. However, some North African communities still recite different Selichot on Mondays, Thursdays and Shabbat, following the order in Siftei Renanot, while keeping the "standard" order on days without Torah Reading. In the Eastern Ashkenazic tradition, although the text and length of specific prayers varies from day to day, the overall format remains the same and is prefaced by Ashrei () and the Half-Kaddish. In the Western Ashkenazic tradition, there is similarly an overall format, but it begins with Adon Olam