Holy Week violet covers during Passiontide, but the crucifix covers can be white instead of violet on Maundy Thursday). Some Protestant churches practice the foot washing (Maundy) ceremony on Maundy Thursday. For others, it may be the only time in the year when Holy Communion is celebrated. Good Friday commemorates the crucifixion of Jesus and his subsequent death. Commemorations of often solemn and mournful, many denominations use Good Friday to perform the Stations of the Cross, or other commemorations of the Passion, either as a self-guided time of reflection and veneration or as a procession of statues or images of the stations.
Armelin's calendar mind of modest ability will learn in a few minutes the weekday with which each month invariably begins, and will be able to compute quickly the day of the week upon which any day of any month falls. Each stated holiday falls upon its invariable day of the week. Thanksgiving Day falls always on November 30. A major disadvantage is for sabbatarians, who are obliged to worship every seventh day. Their holy day will occur on a different weekday every year. Armelin's project received the first premium of the French Astronomical Society. The World Calendar, roughly identical, has been promoted