Reference for Psalms 64:8

וַיֹּרֵ֗ם אֱלֹ֫הִ֥ים חֵ֥ץ פִּתְא֑וֹם הָ֝י֗וּ מַכּוֹתָֽם׃

But God doth shoot at them with an arrow suddenly; thence are their wounds.

ספר השרשים