Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
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1 Samuel 20:3

David swore moreover, and said, “Your father knows well that I have found favor in your eyes; and he says, ‘Don’t let Jonathan know this, lest he be grieved;’ but truly as Yahweh lives, and as your soul lives, there is but a step between me and death.”

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