Male and Female He Created Them and Adam's Long Penance

(Genesis 5:2) "Male and female He created them." Rabbi Elazar said: Any man who has no wife is not a man, as it is said, "Male and female He created them," and so forth. (Genesis 5:3) Rabbi Elazar ben Azaryah said: During all those years that the first Adam was under the ban, he begot demons, spirits, and night-demons, as it is said, "And Adam lived a hundred and thirty years and begot a son in his likeness, after his image" — which implies that until now he did not beget in his image. They raised an objection: Rabbi Meir used to say, the first Adam was a great pious man; once he saw that death had been decreed because of him, he arose and sat in fasting for a hundred and thirty years, and raised growths of fig leaves upon his flesh, and separated from his wife. We speak here of the seed that issued from him against his will. "And Adam lived a hundred and thirty years and begot in his likeness, after his image." From here you learn that Cain was not of his seed, nor of his likeness, nor of his image, until Seth was born. Rabbi Shimon says: From Seth arose and were traced all the generations of the righteous, and so forth. Rabbi Meir says: it was the uncovering of the flesh of nakedness; they walked about like beasts, and so forth. Rabbi Yehoshua says: the angel is a flaming fire, yet the fire enters into intercourse with flesh and blood and does not burn the body; only from the hour that they fell from their place of holiness, their strength and their stature became like that of human beings, and their garments a clod of earth. Rabbi Tzadok says: from them the giants were born, "the Nephilim were in the earth" (Genesis 6:4). Rabbi Yehoshua ben Korchah says: Israel are called sons of God, "You are sons" (Deuteronomy 14:1), and the angels are called sons of God, as it is said (Job 38:7), "When the morning stars sang together," and so forth; and these, while they were in their place of holiness, were called sons of God. "And he begot in his likeness." This teaches that he was born circumcised.