There is a famous story told about the Rogatchover Gaon in regard to the rare times when he disagreed with a decision of the Rambam in Mishneh Torah. It is recounted that the Rogatchover would be distressed not because Rambam was wrong, but that he, the Rogatchover didn’t merit to understand the Rambam’s decisions! Considering the source, if true, that is a very big statement. I heard this story recounted in the name of the Lubavitcher Rebbe who knew and corresponded often with the Rogatchover Gaon.
