Musar על ברכות 13:29

The twelfth: "Which You swore to our fathers" - there are people that are not proper, and the Holy One, blessed be He, has mercy on all of them. And they explained in the Gemara (Berakhot 7a), "and I will give grace to the one that I give grace" (Exodus 33:19) - "The Holy One, blessed be He, said, 'This storehouse is for those that are not proper.'" There is a storehouse of those given grace that the Holy One, blessed be He, graces and gives them [as] a free present. As the Holy One, blessed be He, said, "Behold, they have the merit of the fathers - I swore to the fathers. Therefore, even if they are not proper, they shall merit because they are from the seed of the fathers to whom I swore. Hence, I will lead them and guide them until they are refined."