But it shall come to pass, if thou wilt not hearken unto the voice of the LORD thy God, to observe to do all his commandments and his statutes which I command thee this day; that all these curses shall come upon thee, and overtake thee:
But ... if thou wilt not hearken unto the voice of the Lord. Curses that were to follow them in the event of disobedience are now enumerated; and they are almost exact counterparts to the blessings which were described in the preceding context as the reward of a faithful adherence to the covenant.
The parallel is observed in the particulars specified, Deuteronomy 28:16-19; and the special blessing of Heaven in all their undertakings, promised to faithful and continued obedience, is substituted by an unmitigated curse (Deuteronomy 28:20) overhanging them in every situation.