Charles Ellicott Commentary Deuteronomy 30:10

"if thou shalt obey the voice of Jehovah thy God, to keep his commandments and his statutes which are written in this book of the law; if thou turn unto Jehovah thy God with all thy heart, and with all thy soul." — Deuteronomy 30:10 (ASV)

If thou shalt hearken. —“If” is the Septuagint translation. The Hebrew word signifies “for,” or “when.”