Deuteronomy 17:18

“And it shall be, when he sitteth upon the throne of his kingdom, etc.] When he is settled on it, and is even amidst all the pomp and glory of it: that he shall write him a copy of this law in a book; which copy the Septuagint and Vulgate Latin versions interpret of this book of Deuteronomy, which is a summary abstract and repetition of the various laws of God to the people of Israel; though the Jewish writers commonly understand it of the whole Pentateuch, the five books of Moses; which perhaps may be enlarging it too much, as it would be reducing it to too little to restrain it to this law concerning kings, as the Targum of Jonathan. The word “Mishneh”, rendered “copy”, signifies “double”;…”

“he shall write him a copy of this law in a book--The original scroll of the ancient Scriptures was deposited in the sanctuary under the strict custody of the priests (see on Deu 31:26; Kg2 22:8). Each monarch, on his accession, was to be furnished with a true and faithful copy, which he was to keep constantly beside him, and daily peruse it, that his character and sentiments being cast into its sanctifying mould, he might discharge his royal functions in the spirit of faith and piety, of humility and a love or righteousness.”

“It is in striking consistency with the dignity which everywhere throughout the Mosaic legislation surrounds the chosen people of God, that even if they will be “like as all the nations about” Deuteronomy 17:14, and be governed by a king, care should nevertheless be taken that he shall be no Oriental despot. He is to be of no royal caste, but “one from among thy brethren” Deuteronomy 17:15; he is to bear himself as a kind of “primus inter pares,” his heart “not being lifted up above his brethren” Deuteronomy 17:20; he is, like his subjects, to be bound by the fundamental laws and institutions of the nation, and obliged, as they were, to do his duty in his station of life with constant…”

“He shall write - With his own hand, as the Jews say. Out of that - Out of the original, which was carefully kept by the priests in the sanctuary, that it might be a perfect copy, and that it might have the greater influence upon him, coming to him as from the hand and presence of God. Deuteronomy 17:19”

“17:18 This body of instruction (literally this torah) refers to the book of Deuteronomy or perhaps only to this passage concerning the Israelite monarchy. For torah, see study note on 4:44.”

“that he shall: Kg2 11:12 a copy: Mishneh hattorah hazzoth, "a duplicate of this law." translated by the Septuagint, το δευτερονομιον τουτο, this Deuteronomy. From this version, both the Vulgate and all the modern versions have taken the name of this book; and from it the original word, the Jews call it Mishneh. out of that which: Deu 31:9, Deu 31:25, Deu 31:26; Kg2 22:8; Ch2 34:15 Deuteronomy 17:19”

“And thirdly, instead of hanging his heart upon these earthly things, when he at upon his royal throne he was to have a copy of the law written out by the Levitical priests, that he might keep the law by him, and read therein all the days of his life. כּתב does not involve writing with his own hand (Philo), but simply having it written. הזּאת התּורה משׁנה does not mean τὸ δευτερονόμιον τοῦτο (lxx), "this repetition of the law," as הזּאת cannot stand for הזּה; but a copy of this law, as most of the Rabbins correctly explain it in accordance with the Chaldee version, though they make mishneh to signify duplum, two copies (see Hvernick, Introduction). - Every copy of a book is really a…”