צֹ֣הַר ׀ תַּֽעֲשֶׂ֣ה לַתֵּבָ֗ה וְאֶל־אַמָּה֙ תְּכַלֶ֣נָּה מִלְמַ֔עְלָה וּפֶ֥תַח הַתֵּבָ֖ה בְּצִדָּ֣הּ תָּשִׂ֑ים תַּחְתִּיִּ֛ם שְׁנִיִּ֥ם וּשְׁלִשִׁ֖ים תַּֽעֲשֶֽׂהָ׃
A light shalt thou make to the ark, and to a cubit shalt thou finish it upward; and the door of the ark shalt thou set in the side thereof; with lower, second, and third stories shalt thou make it.
Read kabbalistic (mystical) interpretation of Genesis 6:16: and classical mystical sources.