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

1 Samuel 20:8

Therefore thou shalt deal kindly with thy servant; for thou hast brought thy servant into a covenant of the Lord with thee: notwithstanding, if there be in me iniquity, slay me thyself; for why shouldest thou bring me to thy father?

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