Rabbi Meir Hagar of Viznitz related that one of the great chassidic rabbis was once praying with much enthusiasm. His evil inclination came to him at a moment he was praying with the height of fervor, and whispered in his ear, "How can you be so insolent as to pray in such a manner? Yesterday you did improper things. You are unworthy of such prayers."
The righteous man was not thrown by the evil inclination and mentally replied, "It might be true that yesterday I have erred. Moreover, it is possible that tomorrow once again I might err. But right now I am in the middle of praying, so get away from me!"
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