20 and not consider himself better than his fellow Israelites and turn from the law to the right or to the left. Then he and his descendants will reign a long time over his kingdom in Israel.
20 That his heart be not lifted up above his brethren, and that he turn not aside from the commandment, to the right hand, or to the left: to the end that he may prolong his days in his kingdom, he, and his children, in the midst of Israel.
20 that his heart may not be lifted up above his brothers, and that he may not turn aside from the commandment, either to the right hand or to the left, so that he may continue long in his kingdom, he and his children, in Israel.
20 He must not become proud and arrogant, changing the commands at whim to suit himself or making up his own versions. If he reads and learns, he will have a long reign as king in Israel, he and his sons.
20 that his heart may not be lifted above his brethren, that he may not turn aside from the commandment to the right hand or to the left, and that he may prolong his days in his kingdom, he and his children in the midst of Israel.
20 This regular reading will prevent him from becoming proud and acting as if he is above his fellow citizens. It will also prevent him from turning away from these commands in the smallest way. And it will ensure that he and his descendants will reign for many generations in Israel.
Matthew Henry's Commentary on Deuteronomy 17:20
Commentary on Deuteronomy 17:14-20
(Read Deuteronomy 17:14-20)
God himself was in a particular manner Israel's King; and if they set another over them, it was necessary that he should choose the person. Accordingly, when the people desired a king, they applied to Samuel, a prophet of the Lord. In all cases, God's choice, if we can but know it, should direct, determine, and overrule ours. Laws are given for the prince that should be elected. He must carefully avoid every thing that would turn him from God and religion. Riches, honours, and pleasures, are three great hinderances of godliness, (the lusts of the flesh, the lusts of the eye, and the pride of life,) especially to those in high stations; against these the king is here warned. The king must carefully study the law of God, and make that his rule; and having a copy of the Scriptures of his own writing, must read therein all the days of his life. It is not enough to have Bibles, but we must use them, use them daily, as long as we live. Christ's scholars never learn above their Bibles, but will have constant occasion for them, till they come to that world where knowledge and love will be made perfect. The king's writing and reading were as nothing, if he did not practise what he wrote and read. And those who fear God and keep his commandments, will fare the better for it even in this world.