שִׁבְעַ֥ת יָמִ֖ים תֹּאכַ֣ל מַצֹּ֑ת וּבַיּוֹם֙ הַשְּׁבִיעִ֔י חַ֖ג לַיהוָֽה׃
Seven days thou shalt eat unleavened bread, and in the seventh day shall be a feast to the LORD.
Read kabbalistic (mystical) interpretation of Exodus 13:6: and classical mystical sources.