Why was the mercy seat made of pure, beaten gold?
The mercy seat was pure, beaten gold because it belonged strictly to the realm of the Holy God Himself. It signified God in His holiness, not Christ and His humanity. The beaten gold set apart the place of divine holiness above the Ark of the Covenant.
Les explains that above the hollowed box of the Ark of the Covenant was the mercy seat. He says the mercy seat was pure, beaten gold because this is strictly the area of the Holy God Himself, not Christ and His humanity, but God in His holiness. He then asks what shape the beaten gold was and what overshadowed the mercy seat, leaving those as further Bible study questions.