菩薩修行有可生三種退屈心之難關。見三退屈條。唯識論九曰：「修勝行時有三退屈。」圓覺經曰：「汝善男子！當護末世是修行者，無令惡魔及諸外道惱身心，令生退屈。」
To yield or recede, as is possible to a Bodhisattva facing the hardships of further progress.
一退屈 即退步屈服之心。菩薩修行有三種退屈心之難關，即菩提廣大屈、萬行難修屈、轉依難證屈。對治此三退屈者，稱為三練磨。〔成唯識論卷九〕（參閱「三退屈」820）p5472