"Noah was a righteous man, perfect in his generation; Noah walked with G-d."
In his famous opening comment to parashat Noach, Rashi suggests that possibly Noach was not so great after all. You see, Noah's "righteousness" is balanced or negated by the qualifier: "in his generation." He was a Tzaddik only relative to the sinners of his generation, but had he lived in the era of Avraham, he would have been considered "nothing" of significance.
This is one of a series of Midrashim (Rashi quotes Midrash Rabba 30:9) that denigrate Noah, demoting him from full Tzaddik status to a lower level. Some contrast him with Abraham and others with Moshe:
“R. Berechia said: Moshe is more special than Noach. Noach moved from the status of “a righteous man” (6,9) to “a man of the earth”(9,20), whereas Moshe began as an “Egyptian man”(Ex 2:19) and progressed to become “A man of God”(Deut 33:1)...” Bereshit Rabba 36:3
For many years I was bothered by this. The Torah text says he was a tzaddik. Why can we not follow the text? If you were the most virtuous person in your generation, that would be quite something. why don't Chazal adopt a more generous attitude towards Noach.
Rabbi Dr. Irving Jacobs from Jews’ College, London once gave a historical explanation for this. He explained that these midrashim emerge from the era of early struggle between Christianity and Judaism, in the formative years of Christianity when it was breaking away from Judasim and trying to justify itself vis a vis Judaism.
The Christians broke from traditional Judaism when Paul rejected Mitzvot Ma’asiyot - Halakha. They abandoned the performance of circumcision and kashrut etc. To support their case, they sought out Biblical models - tzaddikim - who were chosen by God despite their NOT keeping Torah MiSinai. Noach was an ideal candidate. He is given the title by the Torah of “Tzaddik” despite the fact that we see no trace of Mitzvot; an ideal role model! They looked to Noach as a justification of their new religion.
How did the Rabbis respond to this “reading” of Noach as a person? In their derashot given in the shuls of Tzippori and Caesarea, and Tiberias the Rabbis responded with a "new reading." If Noach was a Tzaddik, he was a minor one. He could not even approach the level of a Moshe or an Avraham. It was a response to the mood of the age.
Because the Christians venerated Noach, the Rabbis responded by denigrating him, demoting him.
(And methodologically this is a great example of the manner in which historic situations - current events - may create a new p'shat, a new reading, in the passuk. This Rashi is a legitimate reading - to see "in his generation" as regulating and constricting the scope of the appellation "Tzaddik - and yet possibly it was a new way of thinking as Rabbis saw the Christians attach enormous prestige to Noach, they found themselves adopting a different understanding of the text. Maybe this was not even overtly polemical but more subconscious. I think this is a great example of what the Rashbam calls הפשט המתחדש בכל יום.)