Charles Ellicott Commentary Deuteronomy 28:58-59

"If thou wilt not observe to do all the words of this law that are written in this book, that thou mayest fear this glorious and fearful name, JEHOVAH THY GOD; then Jehovah will make thy plagues wonderful, and the plagues of thy seed, even great plagues, and of long continuance, and sore sicknesses, and of long continuance." — Deuteronomy 28:58-59 (ASV)

See Note on Deuteronomy 25:2-3.

This glorious and fearful name, the Lord thy God. —The first Note of the Decalogue is here referred to, as the great curse of the Law draws to its close. It is no light matter when the Almighty says to any people or to any person, I am Jehovah thy God. Those who are His must obey Him, love Him, and acknowledge Him. He will not be mocked. Never did He in all history assay to go and take Him a nation from the midst of other nations as He took Israel. Hence these tremendous consequences.

Of long continuance. —Eighteen hundred years they have lasted, and seem to be breaking out anew now (1882) as though they were in full force. “To chastise you permanently is their mission” (Rashi).