Deuteronomy 17:14-20

14 And when thou shalt enter into the land which the Lord thy God gives thee, and shalt inherit it and dwell in it, and shalt say, I will set a ruler over me, as also the other nations round about me;
15 thou shalt surely set over thee the ruler whom the Lord God shall choose: of thy brethren thou shalt set over thee a ruler; thou shalt not have power to set over thee a stranger, because he is not thy brother.
16 For he shall not multiply to himself horses, and he shall by no means turn the people back to Egypt, lest he should multiply to himself horses; for the Lord said, Ye shall not any more turn back by that way.
17 And he shall not multiply to himself wives, lest his heart turn away; and he shall not greatly multiply to himself silver and gold.
18 And when he shall be established in his government, then shall he write for himself this repetition of the law into a book by the hands of the priests the Levites;
19 and it shall be with him, and he shall read in it all the days of his life, that he may learn to fear the Lord thy God, and to keep all these commandments, and to observe these ordinances:
20 that his heart be not lifted up above his brethren, that he depart not from the commandments on the right hand or on the left; that he and his sons may reign long in his dominion among the children of Israel.

Footnotes 2

The Brenton translation of the Septuagint is in the public domain.