וַיִּנָּ֣חֶם יְהוָ֔ה כִּֽי־עָשָׂ֥ה אֶת־הָֽאָדָ֖ם בָּאָ֑רֶץ וַיִּתְעַצֵּ֖ב אֶל־לִבּֽוֹ׃
And it repented the LORD that He had made man on the earth, and it grieved Him at His heart.
Read kabbalistic (mystical) interpretation of Genesis 6:6: and classical mystical sources.