Story Source

[Skull]

A friend recalls this outline of the tale:

As I recall it as a Hindu (or Buddhist?) story about a man who approached a Master and asked how long it would take him to attain Nirvana. The Guru told him it would take him one lifetime of perfect conduct or 100 years of destructive conduct. The man for whom even one day of perfection was beyond him, rejoiced, for "a hundred years will pass as a day, if by it I will attain Enlightenment"

I cannot help her, for I am not familiar with the story; anyone here know the story and the source?