וַיִּוָּֽעֲצוּ֙ כָּל־הַקָּהָ֔ל לַעֲשׂ֕וֹת שִׁבְעַ֥ת יָמִ֖ים אֲחֵרִ֑ים וַיַּֽעֲשׂ֥וּ שִׁבְעַת־יָמִ֖ים שִׂמְחָֽה׃
And the whole congregation took counsel to keep other seven days; and they kept other seven days with gladness.
Read kabbalistic (mystical) interpretation of II Chronicles 30:23: and classical mystical sources.