Seder HaYom, meaning “Order of the Day,” was written by Rabbi Moshe ben Machir, a 16th-century halakhist and kabbalist of the Safed region. The book lays out a daily program of prayer and other behaviors, including holiday rituals, Torah study, and interpersonal commandments such as visiting the sick, and is intended to guide the average individual toward the best use of time throughout each day and year, with the fundamental goal of fulfilling God’s will. The work includes commentary and instructions regarding performance as well as accompanying devotions. It is the earliest source of several customs, most notably the popular Modeh Ani prayer, an expression of gratitude recited immediately upon awakening each day.