Reference for Psalms 18:8

וַתִּגְעַ֬שׁ וַתִּרְעַ֨שׁ ׀ הָאָ֗רֶץ וּמוֹסְדֵ֣י הָרִ֣ים יִרְגָּ֑זוּ וַ֝יִּתְגָּֽעֲשׁ֗וּ כִּי־חָ֥רָה לֽוֹ׃

Then the earth did shake and quake, the foundations also of the mountains did tremble; they were shaken, because He was wroth.

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