Matthew Henry on Leviticus 27:1-13

Zeal for the service of God disposed the Israelites, on some occasions, to dedicate themselves or their children to the service of the Lord, in his house for life. Some persons who thus dedicated themselves might be employed as assistants; in general they were to be redeemed for a value. It is good to be zealously affected and liberally disposed for the Lord's service; but the matter should be well weighed, and prudence should direct as to what we do; else rash vows and hesitation in doing them will dishonour God, and trouble our own minds.