It states (Bereishis 6:8) 'ה בעיני חן מצא ונח, "Noach found favor in the eyes of Hashem." What did Noach do to receive chen, favor in Hashem's eyes?
The Or HaChaim says, "There is a single mitzvah or perhaps three or four mitzvos that are mesugal for chen." Noach performed those mitzvos, and Hashem found chen in him (however, the Or HaChaim doesn't specify which mitzvos are mesugal for chen).
Some say, as we wrote above, that Noach had emunah that everything occurs 'ה בעיני, according to Hashem's hashgachah pratis, and with this emunah, he attained chen in Hashem's eyes.
The Ben Ish Chai (Ben Yehoyada, Beitzah 16.) writes that bitachon is mesugal for chen. The hint is that the word בטחון is comprised of two words: טוב- חן. "With בטחון, one merits חן and טוב, chen and Hashem's kindness." This is hinted in the pasuk (Tehillim 84:12), יתן וכבוד חן בתמים להולכים טוב ימנע לא 'ה, "Hashem will give chen and honor; He will not withhold good from those who go with bitachon."
The Chareidim (Mitzvas Asei 1) writes, "Noach was always calm and tranquil. It states, 'ה בעיני חן מצא ונח, and the Midrash explains that his calm and tranquil attitude found favor with Hashem. This is because tranquility comes from the side of kedushah, and anger comes from the side of tumah." So, according to the Chareidim, Noach found favor in Hashem's eyes because of his nature of נח, calmness, and avoidance of anger.
The Gemara (Succah 49:) states, "If a person has chen, you can be certain that he fears Hashem." So, we have another explanation of how Noach attained chen. Noach had chen because of his yiras Shamayim.
