Harshness and Shame of a person undergoing Hashem's judgment: Chagigah 4b, 5a
When one brother or member of a group dies, the rest should worry: Shabbat 105b-106a
Punishment for nochrim who sin: Megillah 12b
One who accepts his suffering with joy brings salvation to the world: Taanit 8a
Bringing a korban asham taluy to forestall punishment if one is uncertain whether he sinned; he will bring a korban chatat when he finds out that he definitely sinned: Keritot 25a-b, 26b