וַיַּ֣רְא פַּרְעֹ֗ה כִּ֤י הָֽיְתָה֙ הָֽרְוָחָ֔ה וְהַכְבֵּד֙ אֶת־לִבּ֔וֹ וְלֹ֥א שָׁמַ֖ע אֲלֵהֶ֑ם כַּאֲשֶׁ֖ר דִּבֶּ֥ר יְהוָֽה׃ (ס)
But when Pharaoh saw that there was respite, he hardened his heart, and hearkened not unto them; as the LORD had spoken.
Read kabbalistic (mystical) interpretation of Exodus 8:11: and classical mystical sources.