וַיְהִ֤י כַחוֹל֙ זַרְעֶ֔ךָ וְצֶאֱצָאֵ֥י מֵעֶ֖יךָ כִּמְעֹתָ֑יו לֹֽא־יִכָּרֵ֧ת וְֽלֹא־יִשָּׁמֵ֛ד שְׁמ֖וֹ מִלְּפָנָֽי׃
Thy seed also would be as the sand, And the offspring of thy body like the grains thereof; His name would not be cut off Nor destroyed from before Me.
Rashi on Isaiah
like its innards of the sea, like the fish of the sea for multitude.