A.T. Robertson Commentary Matthew 2:11

"And they came into the house and saw the young child with Mary his mother; and they fell down and worshipped him; and opening their treasures they offered unto him gifts, gold and frankincense and myrrh." — Matthew 2:11 (ASV)

Opening their treasures (ανοιξαντες τους θησαυρους αυτων). Here "treasures" means "caskets" from the verb (τιθημ), receptacle for valuables. In the ancient writers it meant "treasury" as in 1Macc. 3:29. So a "storehouse" as in Mt 13:52. Then it means the things laid up in store, treasure in heaven (Matthew 6:20), in Christ (Colossians 2:3). In their "caskets" the Magi had gold, frankincense, and myrrh, all found at that time in Arabia, though gold was found in Babylon and elsewhere.