The Gemara (Bab. Shab. 55a) discusses when Zechuth Avoth ceased. I am aware of several opinions in Tosafoth that it ended for wicked people, or it ended for everyone but the very righteous or it ended but Berith Avoth didn't end - whatever that means. But - what does that mean? So much of our religious culture seems to assume that we are still in G-d's good graces because of the merits of our forefathers! What does it mean if we've used up that merit?! On what basis are we waiting for redemption, for one thing? On what basis do we pray for mercy and favor, for another thing? But my question is broader - generally, what does it mean for us not to have that merit in our favor?
This question is part of the Daf Yomi Challenge