וַיִּרְא֕וּ אֵ֖ת אֱלֹהֵ֣י יִשְׂרָאֵ֑ל וְתַ֣חַת רַגְלָ֗יו כְּמַעֲשֵׂה֙ לִבְנַ֣ת הַסַּפִּ֔יר וּכְעֶ֥צֶם הַשָּׁמַ֖יִם לָטֹֽהַר׃
and they saw the God of Israel; and there was under His feet the like of a paved work of sapphire stone, and the like of the very heaven for clearness.
Siddur Ashkenaz
Sanctify them with you commandments, and make them as pure as the very sky