Numbers 3:1 Kabbalah

וְאֵ֛לֶּה תּוֹלְדֹ֥ת אַהֲרֹ֖ן וּמֹשֶׁ֑ה בְּי֗וֹם דִּבֶּ֧ר יְהוָ֛ה אֶת־מֹשֶׁ֖ה בְּהַ֥ר סִינָֽי׃

Now these are the generations of Aaron and Moses in the day that the LORD spoke with Moses in mount Sinai.

Read kabbalistic (mystical) interpretation of Numbers 3:1: and classical mystical sources.