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

Isaiah 9:6

His government shall be great, and of his peace there is no end: [it shall be] upon the throne of David, and [upon] his kingdom, to establish it, and to support [it] with judgment and with righteousness, from henceforth and for ever. The zeal of the Lord of hosts shall perform this.

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