Charles Spurgeon Commentary Exodus 25:18-20

"And thou shalt make two cherubim of gold; of beaten work shalt thou make them, at the two ends of the mercy-seat. And make one cherub at the one end, and one cherub at the other end: of one piece with the mercy-seat shall ye make the cherubim on the two ends thereof. And the cherubim shall spread out their wings on high, covering the mercy-seat with their wings, with their faces one to another; toward the mercy-seat shall the faces of the cherubim be." — Exodus 25:18-20 (ASV)

They were part and parcel of the mercy-seat; they were made of the same precious metal, and all formed one piece. They may represent the angels, who stand desiring to look into the mysteries of God, and they may also represent the Church, which is indivisibly one with Christ, forever one with him.