Zikaron leYom Rishon is a collection of High Holiday sermons delivered by the religious postmodern Israeli thinker Rav Shimon Gershon Rosenberg, known as Rav Shagar for his acronym. Drawing on traditional legal sources, philosophy, and chasidic thought, the work addresses concepts such as sin, guilt, forgiveness, and compassion, aiming to connect them to lived human experience.