Charles Ellicott Commentary Leviticus 27:17

"If he sanctify his field from the year of jubilee, according to thy estimation it shall stand." — Leviticus 27:17 (ASV)

If he sanctify his field from the year of jubile. —That is, the above-named valuation of fifty shekels only applies if he makes the vow immediately after the expiration of the year of jubile, when the period covered by this estimation is forty-nine years.