It is one of the holiest observances and known as the "Sacrifice Feast” honors the willingness of Abraham to sacrifice his son, as an act of submission to God's command. In commemoration, an animal is sacrificed and divided into three parts: the family retains one third of the share another third is given to relatives, friends and neighbors and the remaining third is given to the poor and needy. Some Muslims determine the start of the observance by naked-eye sighting of the location of the moon.