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

Zechariah 8:9

Thus saith the Lord of hosts; Let your hands be strong, ye that hear in these days these words by the mouth of the prophets, which were in the day that the foundation of the house of the Lord of hosts was laid, that the temple might be built.

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