Hattarat Nedarim (absolution from vows) according to the custom of Baghdad as instucted by the Hida. The liturgy is to be said erev Rosh Ha-Shanah and erev Yom ha-Kippur before a quorum of ten or in the alternative three scholars. The text varies from the current text of Hattarat Nedarim and includes considerable material (tefillot) calling on the name of G-d not in standard siddurim.
The enormous importance of the vow and its serious consequences are reflected in the fact that a whole tractate of the Talmud, consisting of 11 chapters in the Mishnah and 91 folios in the Gemara, is devoted to it, excluding the Nazirite vow, to which a separate tractate is devoted. The biblical laws of vowing are to be found in Numbers 30: 1–16. No explicit provision is made there for absolution from vows (hattarat nedarim), the Bible permitting only the voiding of a vow (hafarat nedarim) in the case of an unmarried woman by her father, and a married woman by her husband, providing he did so "in the day that he heareth." Nevertheless, the rabbis evolved an elaborate machinery for the absolution of vows, although they frankly admitted that "the rules about the absolution of vows hover in the air and have nothing to support them" (Hag. 1: 8).