The Ark of the Covenant, also known as the Ark of the Testimony or the Ark of God, is believed to have been the most sacred religious relic of the Israelites. It is described as a wooden chest coated in pure gold and topped off by an elaborate golden lid known as the mercy seat. According to the Book of Exodus and First Book of Kings in the Hebrew Bible and the Old Testament, the Ark contained the Tablets of the Law, by which God delivered the Ten Commandments to Moses at Mount Sinai. According to the Book of Exodus, the Book of Numbers, and the Epistle to the Hebrews in the New Testament, it also contained Aaron's rod and a pot of manna.

According to the Hebrew Bible, the kaporet or mercy seat was the gold lid placed on the Ark of the Covenant, with two cherubim at the ends to cover and create the space in which Yahweh appeared and dwelled. This was connected with the rituals of the Day of Atonement. The term also appears in later Jewish sources, and twice in the New Testament, from where it has significance in Christian theology.