(ו) וַיִּנָּ֣חֶם יְהוָ֔ה כִּֽי־עָשָׂ֥ה אֶת־הָֽאָדָ֖ם בָּאָ֑רֶץ וַיִּתְעַצֵּ֖ב אֶל־לִבּֽוֹ׃
Genesis 6:6
(6) And it repented the LORD that He had made man on the earth, and it grieved Him at His heart.
6. And the Lord regretted that He had made man on earth, and His heart was saddened (JPS)
6 Then YHVH was sorry that he had made humankind on earth, and it pained his heart. (Everett Fox)
(1) 'וינחם ה, the expression, וינחם, “He was sorry, He regretted,” has been chosen by the Torah in order for human beings to have at least an inkling of what G’d’s feelings were when He faced destroying His handiwork. Clearly, such emotions as “regret” are not part of G’d’s vocabulary. We have it on the authority Samuel I 15 29 that human feelings such as regret, frustration, are not feelings which can be attributed To Him.
Rabbi David Kimhi, 1160-1235, France
(24) This is why in the future when the world will be full of knowledge of the Lord-a spiritual achievement-also physical matter such as the body will benefit through resurrection. It too will be able to absorb such knowledge. This is one of the important aspects in which the present sin-polluted world differs from an ideal world. The inferior status of matter in our world had its origin in Genesis 6,6, where the Torah says: ויתעצב אל לבו, He (G'd) was saddened concerning his (man's) heart. G'd saw that man no longer was using his body correctly, that the only area of spirituality left was man's heart. If man had "seen" with his heart instead of merely with his "eyes," [part of physical matter. Ed.] man's fall could have been avoided. We know from Samuel I 16,7: "for man 'sees' with the eyes whereas G'd 'sees' with the heart." Only G'd sees with His "heart." Man's decline began when the tree of knowledge appealed to Eve's eyes (Genesis 3,6).
Shney Luchot Habrit by Rabbi Isaiah Horowitz, 1565-1630, Prague
(ב) ויתעצב. האדם:
(ד) ויתעצב אל לבו. נתאבל על אבדן מעשה ידיו, כמו (ש"ב יט ג) נעצב המלך על בנו וזו כתבתי לתשובת המינים, גוי אחד שאל את רבי יהושע בן קרחה, אמר לו אין אתם מודים שהקדוש ברוך הוא רואה את הנלד, אמר לו הן. אמר לו והא כתיב ויתעצב אל לבו, אמר לו נלד לך בן זכר מימיך, אמר לו הן. אמר לו ומה עשית, אמר לו שמחתי ושמחתי את הכל. אמר לו ולא היית יודע שסופו למות, אמר לו בשעת חדותא חדותא, בשעת אבלא אבלא. אמר לו כך מעשה הקדוש ברוך הוא, אף על פי שגלוי לפניו שסופן לחטוא ולאבדן לא נמנע מלבראן בשביל הצדיקים העתידים לעמוד מהם:
and He became grieved: [I.e.,] man
...and He became grieved: Heb. וַיִּתְעַצֵּב, He mourned over the destruction of His handiwork [i.e., according to this second view, וַיִּתְעַצֵּב refers to God], like (II Sam. 19:3): “The king is saddened (נֶעֱצַב) over his son.” This I wrote to refute the heretics: A gentile asked Rabbi Joshua ben Korchah, “Do you not admit that the Holy One, blessed be He, foresees the future?” He [Rabbi Joshua] replied to him, “Yes.” He retorted, “But it is written: and He became grieved in His heart!” He [Rabbi Joshua] replied, “Was a son ever born to you?” “Yes,” he [the gentile] replied. “And what did you do?” he [Rabbi Joshua] asked. He replied, “I rejoiced and made everyone rejoice.” “But did you not know that he was destined to die?” he asked. He [the gentile] replied, “At the time of joy, joy; at the time of mourning, mourning.” He [Rabbi Joshua] said to him, “So is it with the work of the Holy One, blessed be He; even though it was revealed before Him that they would ultimately sin, and He would destroy them, He did not refrain from creating them, for the sake of the righteous men who were destined to arise from them.” - [from Gen. Rabbah 27:4]
Rabbi Shlomo Yitzchaki, 1040-1105, France