Deuteronomy 28:59 in the World English Bible
then the LORD will make your plagues and the plagues of your offspring fearful, even great plagues, and of long duration, and severe sicknesses, and of long duration.
Context
58 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, THE LORD THY GOD;
59 Then the LORD 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.
60 Moreover he will bring upon thee all the diseases of Egypt, which thou wast afraid of; and they shall cleave unto thee.