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

2 Samuel 12:18

And it came to pass on the seventh day, that the child died. And the servants of David feared to tell him that the child was dead: for they said, Behold, while the child was yet alive, we spake unto him, and he would not hearken unto our voice: how will he then vex himself, if we tell him that the child is dead?

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