Rabbah, Abaye and the Curse of Eli
Descendants of Eli were cursed to die young, yet Rabbah's Torah earned him 40 years and Abaye's Torah and chesed earned him 60.
Due to improprieties committed by the sons of Eli, a Kohein Gadol, Hashem proclaimed a curse on his descendants that they would die young. Unless some special exception was made, the descendants wouldn’t live past 20. The Talmud relates that two great sages, Abaye and Rabbah, descended from Eli. Rabbah lived until 40. Abaye lived until 60. The Gemara explains that Rabbah learned and taught Torah; therefore, 20 years were added to his life. Abaye performed acts of kindness as well as learning and teaching Torah; therefore, 40 years were added to his life (Yevamos 105a).