Midras Pengkhotbah 6:1: Aggadat Bereshit

[4] Another interpretation: the HaShem saw that the wickedness of man was great in the earth, and that every inclination of the thoughts of his heart was only evil continually." (Genesis 6:5) Similarly, it is written in Ecclesiastes 6:1, "There is an evil which I have seen under the sun, and it is common among men." The Holy One, blessed be He, said, "Behold what these wicked people do! When I created them, I gave each of them two suns, one good and one bad, and they forsake the good sun and cling to and associate with the bad. And from where do we learn this? As Solomon said in Proverbs 21:1, 'The king's heart is like channels of water in the hand of the Lord; He directs it wherever He wants.' Just as the king can turn water in any direction he wishes, so too can the Holy One, blessed be He, turn the hearts of man in any direction He desires. And as we find that Solomon said, 'There was a small city with few men in it, and a great king came against it, and besieged it and built great bulwarks against it' (Ecclesiastes 9:14), so too does the Holy One, blessed be He, surround and punish the wicked for their evil deeds." The small city is the body, the few men in it are the organs, the great king is the evil inclination (yetzer hara), and the siege works are the great temptations that the evil inclination uses to ensnare man. But there was found in it a poor (and wise) man (ibid.). This is the good inclination (yetzer tov), who with his wisdom saves the city. The good inclination guides man towards a good and righteous path of life, and man does not remember that poor man (the good inclination). God said: "These wicked people not only did not follow their evil inclination, but they also perverted their good inclination and made it evil, as it is written: 'And every inclination of the thoughts of his heart was only evil continually' (Genesis 6:5)." This is the end of the Torah portion.