Deuteronomy 28:39
Thou shalt plant vineyards, and dress them, but shalt neither drink of the wine, nor gather the grapes; for the worms shall eat them. Thou shalt plant vineyards, and dress them, but shalt neither drink of the wine, nor gather the grapes; for the worms shall eat them.
The verse pronounces the loss of a vineyard's harvest as a curse for disobedience, that a person will plant and dress vines but will neither drink of the wine nor gather the grapes because worms will eat them. The labor yields no benefit, for the crop is destroyed and cannot be enjoyed, bringing a curse upon the land and its crops. It belongs among the curses Moses set against Israel for failing to obey God, placed alongside the blessings of obedience to show that obedience brings prosperity while disobedience brings loss. The Lord's promises and blessings are conditional upon obedience.
Moses read it aloud to all Israel assembled before him from the book he had written, together with God's promises to them if they would be obedient and the events of their past history. Those curses include the nation's later overthrow and the destruction of Jerusalem by Rome. The chapter shows why the adults of the army that left Egypt were refused entry into the promised land.
God sends prosperity or adversity according to obedience to or transgression of His law, so Israel's success or defeat depends on obedience rather than merely possessing the ark, which contains the law and represents God's presence. Transgressing God's law breaks down the barriers He erected to preserve His people from disease and brings suffering and loss. Diligently listening to His voice and doing what is right and keeping His commandments and statutes keeps them in health and holiness under the protection and healing power of Christ.
The verse belongs to Deuteronomy 26-28, which plainly state the blessings of obedience and express the principles of the law of God's kingdom made specific so that minds are not left in ignorance and uncertainty. They lay a never-ceasing obligation on all whom God has blessed with life and health and temporal and spiritual advantages. The message has not grown weak because of age, for God's claims are just as binding now and just as fresh in importance as His gifts are fresh and continual. The voice speaking them is the voice of Christ from the enfolding pillar of cloud, and Christ has repeated them with His own voice, calling His followers to a life of consecration and self-denial.