Matthew Poole's English Annotations on the Holy Bible - 1 Chronicles 23:3
From the age of thirty years and upward; not only till fifty, as it was appointed, Numbers 4:2,Numbers 4:3, but even till their death; for that was but a temporary law grounded upon a special reason, because the Levites were employed in carrying the tabernacle and sacred vessels from place to place; and therefore God would have them freed from those burdens when they came to feel the infirmities of age; which reason wholly ceasing upon the building of the temple, and their work being far easier... read more
Matthew Poole's English Annotations on the Holy Bible - 1 Chronicles 23:2
Partly to declare God’s mind and his own will, that Solomon should be his successor; and so to cut off the claims and pretences which others of his sons might make to the crown; and partly to acquaint them with those directions which he had received from God by the Spirit, as appears from 1 Chronicles 28:11, &c., concerning the establishment of a new order and method in the ministration of the priests and Levites in the temple. read more