Either these are the same kind of treasures, the latter phrase only explaining the former, the particle and being used for that is; or rather, they are two different kinds of treasures, the former containing the sacred vessels and other treasures, which by God's command were appropriated to the maintenance of the house, and worship, and ministers of God, as tithes, and first-fruits, and other things; and the latter only those things which had been freely given or dedicated to God for those ends; of which 1 Chronicles 26:26,27.
Related Commentaries of 1 Chronicles 26:20
1 Chronicles 26:20
20 And of the Levites, Ahijah was over the treasures of the house of God, and over the treasures of the dedicated things.