(Psa 7:9 KJV) Oh let the wickedness of the wicked come to an end; but establish the just: for the righteous God trieth the hearts and reins.
(Proverbs 5 also read)
The NASB has an ending that is different.
(Psa 7:9 NAS77) O let the evil of the wicked come to an end, but establish the righteous; For the righteous God tries the hearts and minds.“Reins” (3629)? “Hearts” (3629)? What? A little bit of enlightenment is thrown in by the NASB marginal reading that says, “Literally kidneys”. If the Hebrew is “kidneys” why not translate it kidneys? I imagine the answer would be that they did not want children and teenagers giggling at the reading of Psalms. I understand their motive but I resent their condescending attitude.
The NASB is probably more modern in its understanding which actually gives the KJV a great advantage. When you read “reins” you start scratching your head and wondering what they are talking about. If your vocabulary is broad enough you recognize that reins are what you control horses with if you are driving a stage coach. That should startle you enough that you start to think about what God is trying to say.
Maybe “the reins of the heart” would be even better. The word is referring to the innermost part of your personhood, that which guides you priorities and decisions. Since moderns tend to think of the heart in terms of emotion the old English gets us deeper.
So? One reason I don’t worry about the perseverance of the saints for my life is that I know God looks deep down in my heart and sees what reins me in. He does not look at my long record of failure as much as my constant desire to do His will. I can live with that.