בְּטֶ֤רֶם ׀ הָ֘רִ֤ים יֻלָּ֗דוּ וַתְּח֣וֹלֵֽל אֶ֣רֶץ וְתֵבֵ֑ל וּֽמֵעוֹלָ֥ם עַד־ע֝וֹלָ֗ם אַתָּ֥ה אֵֽל׃
Before the mountains were brought forth, Or ever Thou hadst formed the earth and the world, Even from everlasting to everlasting, Thou art God.
Read halakhic rulings (Jewish law) on Psalms 90:2: and classical halakhic sources.