מִזְבַּ֣ח אֲדָמָה֮ תַּעֲשֶׂה־לִּי֒ וְזָבַחְתָּ֣ עָלָ֗יו אֶת־עֹלֹתֶ֙יךָ֙ וְאֶת־שְׁלָמֶ֔יךָ אֶת־צֹֽאנְךָ֖ וְאֶת־בְּקָרֶ֑ךָ בְּכָל־הַמָּקוֹם֙ אֲשֶׁ֣ר אַזְכִּ֣יר אֶת־שְׁמִ֔י אָב֥וֹא אֵלֶ֖יךָ וּבֵרַכְתִּֽיךָ׃
An altar of earth thou shalt make unto Me, and shalt sacrifice thereon thy burnt-offerings, and thy peace-offerings, thy sheep, and thine oxen; in every place where I cause My name to be mentioned I will come unto thee and bless thee.
Read kabbalistic (mystical) interpretation of Exodus 20:21: and classical mystical sources.