15 thou dost certainly set over thee a king on whom Jehovah doth fix; from the midst of thy brethren thou dost set over thee a king; thou art not able to set over thee a stranger, who is not thy brother.
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.
Matthew Henry's Commentary on Deuteronomy 17:15
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.