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

1 Samuel 17:13

And the three eldest sons of Jesse went and followed Saul to the battle: and the names of his three sons that went to the battle were Eliab the firstborn, and next unto him Abinadab, and the third Shammah.

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