With the arrival of Rosh Hodesh Elul we enter the month of “mercy and forgiveness.” Among the season’s most well-known but challenging customs is the recitation of Selihot. The publication of a new edition of these penitential prayers and piyutim, with an introduction and insightful commentary by Rabbi Jacob J. Schacter, will enhance our recitation of the Selihot for generations to come. In this excerpt R. Schacter explores themes related to the meaning and force of the Thirteen Attributes of Mercy – the central experience of the Selihot prayers.