Zohar, Prologue: Verse 40
בְּרֵאשִׁית, רַבִּי יוּדָאי אֲמַר, מַאי בְּרֵאשִׁי"ת, בְּחָכְמָ"ה, דָּא חָכְמָ"ה דְּעָלְמָא קָיְימָא עֲלָהּ לְעָאלָא גוֹ רָזִי סְתִימִין עִלָּאִין. וְהָכָא אִגְלִיפוּ שִׁית סִטְרִין רַבְרְבִין עִלָּאִין, דְּמִנְהוֹן נָפֵיק כֹּלָא, דְּמִנְהוֹן אִתְעֲבִידוּ שִׁית מְקוֹרִין וְנַחֲלִין לְעָאלָא גוֹ יַמָּא רַבָּא. וְהַיְינוּ בָּרָא שִׁי"ת, מֵהָכָא אִתְבְּרִיאוּ. מַאן בָּרָא לוֹן הַהוּא דְּלָא אִדְכַּר, הַהוּא סָתִים דְּלָא יְדִיעַ.

Beresheet. Rabbi Yudai asks, What is Beresheet? It means 'with wisdom'. And this is the wisdom upon which the world, WHICH IS THE SECRET OF ZEIR ANPIN, is established and allowed to enter the deep and secretive mysteries, NAMELY THE LIGHTS OF BINAH. Here the six supernal directions are engraved, WHICH ARE THE SIX EXTREMITIES OF BINAH, from which everything emerges. From them were formed the six sources and rivers, WHICH ARE THE SIX EXTREMITIES OF ZEIR ANPIN that flow into the great sea, WHICH IS MALCHUT. THEREFORE, Bara Sheet (Eng. 'He created six') SUGGESTS THE SIX LETTERS OF BERESHEET, FOR THE SIX EXTREMITIES were created from here. And who created them? He who is not mentioned; He who is concealed and unknown, WHO IS CALLED ARICH ANPIN.