The maniple is a vestment of embroidered silk or similar fabric that when worn, hangs from the left forearm. It is only used during a Mass, and it is of the same liturgical color as the other vestments. When used, maniples can be worn by the celebrant, deacon, and subdeacon, but only when these clergy are vested in a chasuble, dalmatic, and tunicle, respectively, during the celebration of the Mass. Following the reforms of Vatican II, the maniple was made optional for Catholic clergy. In the 6th century, the maniple was a piece of cloth which clerics used to wipe their faces and hands, and some pundits have described it as being akin to a handkerchief. Some liturgists refer to the maniple’s likeness to the ropes by which Christ was led. It is also associated with tears of penance. Pre-Medieval writings describe the maniple being used to wipe away the almost continual tears that flowed from the eyes of the grieving priest during Mass.
~ Dr. Gil Haas, St. Augustine of Canterbury Episcopal Church