Charles Spurgeon Commentary Numbers 8:13-14

"And thou shalt set the Levites before Aaron, and before his sons, and offer them for a wave-offering unto Jehovah. Thus shalt thou separate the Levites from among the children of Israel; and the Levites shall be mine." — Numbers 8:13-14 (ASV)

We are to offer up to God our spirit, soul and body, which is our reasonable service; and if we are indeed God's children, we are to feel that, from now on, we are not our own, for we are bought with a price. We belong wholly to God; all that we are, and all that we have, is to be his through life, and in death, and throughout eternity.