What Is Maundy Thursday?
On Holy Thursday (also called Maundy Thursday), Christians commemorate the Last Supper—a Passover meal that Jesus shared with his disciples the night before his death. During the meal, Jesus broke bread and offered his followers wine, saying “This is my body, given up for you.” Many Christians consider this event to have been the institution of the Eucharist, which is a sacrament in some denominations.
Read more at https://www.beliefnet.com/faiths/christianity/2007/03/faq-christian-holidays-during-holy-week.aspx#qgU1x3fTK2YFIzGD.99
Brief explanations of important Christian holidays during the week before Easter such as Palm Sunday, Maundy Thursday and Good Friday