Leviticus 27:33, commentary and pictures

The tenth animal of the herd and flock that passes under the shepherd's rod is set apart as holy and belongs to the Lord. No searching is to be made whether it be good or bad, and no change or substitution is to be made. If an exchange is made at all, both the original animal and the change thereof become holy and shall not be redeemed. All that people possess remains God's own property and is only lent to them in trust, including physical and mental powers and capital of means, and is not to be used as if it were their own.

The required return is His claimed portion as rental money for His vineyard entrusted to His husbandmen as caretakers, to be faithfully returned to Him. That vineyard is to be cultivated so as to bring Him a large income in tithes and offerings. The tenth is sacred and belongs to God, not an optional gift, and withholding it is robbery; it is the least He claims, with gifts and offerings expected in addition to it. The tithing system is a definite plan reaching back before Moses, yet giving under it remains voluntary and is not compelled.

The set-apart portion is for sustaining the ministry and is to be used for no other purpose, while gifts and offerings relieve the necessities of the church and provision is made for the poor and suffering. This consecration of the tithe from flocks and herds keeps continually before the people that all belongs to Him. It trains them to resist selfishness and to become channels of blessing. Failure to return the tenth stands recorded as unfaithful handling of property entrusted to them, and repentance requires more than merely beginning to tithe correctly from that time onward.