mercy seat. propitiatory cover (Hebrew. kapporeth. cover). By Figure of speech Metonymy (App-6) cover put for the propitiation made through the blood sprinkled thereon. It therefore denotes propitiation. Compare Hebrews 9:5. Hence the meaning, God's "propitiatory gift", as in Papyri. Compare Romans 3:25.
pure gold. Not overlaid, because propitiation is. Divine work throughout.