Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
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Exodus 15:26

He said, “If you will diligently listen to Yahweh your God’s voice, and will do that which is right in his eyes, and will pay attention to his commandments, and keep all his statutes, I will put none of the diseases on you which I have put on the Egyptians; for I am Yahweh who heals you.”

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