Old Testament readings use the Septuagint , the Scripture the apostles quoted. Masoretic numbering shown for reference.Learn why
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2 Esdras 6:50

You separated the one from the other; for the seventh part, namely, where the water was gathered together, might not hold them both.

Parallel Translations

KJVView canonical →
And didst separate the one from the other: for the seventh part, namely, where the water was gathered together, might not hold them both.
King James Version