Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
KJV

Isaiah 59:21

As for me, this is my covenant with them, saith the Lord; My spirit that is upon thee, and my words which I have put in thy mouth, shall not depart out of thy mouth, nor out of the mouth of thy seed, nor out of the mouth of thy seed’s seed, saith the Lord, from henceforth and for ever.

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