Charles Ellicott Commentary Leviticus 27:2

"Speak unto the children of Israel, and say unto them, When a man shall accomplish a vow, the persons shall be for Jehovah by thy estimation." — Leviticus 27:2 (ASV)

Shall make a singular vow. —Better, shall consecrate a vow .

According to the interpretation of this phrase that prevailed during the second Temple, it denotes shall pronounce a vow. Therefore, the ancient Chaldee Versions render it, “shall distinctly pronounce a vow.”

Consequently, no vow mentally made or conceived was considered binding; it had to be distinctly pronounced in words.

The form of the vow is nowhere given in the Bible. Like many other points of detail, its wording was left to the administrators of the law.

They divided vows into two classes:

1. Positive vows, by which a man bound himself to consecrate for religious purposes his own person, those members of his family over whom he had control, or any portion of his property. For this kind of vow, the formula was: “Behold I consecrate this to the Lord.”
2. Negative vows, by which he promised to abstain from enjoying a certain thing. For this, the formula was: “Such and such a thing be unlawful to me for so many days, weeks, or forever.”

The persons shall be for the Lord by thy estimation. —Better, souls to the Lord according to thy estimation.

That is, the vow consists of consecrating persons to the Lord with the intention of redeeming with money the persons thus consecrated, according to the valuation placed upon them by Moses.

This part of the verse explains the nature of the vow and assumes that consecrating a human being to God by a vow means substituting their money value.

By the suffix “thy estimation,” Moses is referred to, to whom these regulations are Divinely communicated here, and on whom it devolved initially to carry out the law (see Leviticus 5:15, 18).

During the second Temple period, any Israelite could estimate the money value of a person vowed in this way to the Lord.