Deuteronomy 17:18

A copy of this law] i.e. not merely the law of the kingdom contained in Deuteronomy 17:14, but the entire Deuteronomio law which is in the custody of the priests: see on Deuteronomy 31:9; Deuteronomy 31:24. At the coronation of Josiah the 'testimony' was put into his hands (2 Chronicles 23:11); and to this day, when a Christian monarch is crowned, the Bible is delivered to him with the words: 'We present you with this book, the most valuable thing that the world affords. Here is wisdom; this is the royal law: these are the lively (i.e. living) oracles of God,' signifying that the law of God is to be the rule of his kingdom. In LXX the words a copy of this law are represented by the single word 'deuteronomion,' from which the title of the whole book is derived: see Intro. § 1.