The old rebbe brings a saying from the Talmud: 'whoever reviews what he learned one hundred times, is call one who does not work on himself. But the one who reviews what he learned a hundred and one times, is called one who works for G-d. And the rebbe explains: in the past, they would review what they learned one hundred times, and it was natural, and therefore the one who reviews on hundred times, does not put in it a real work, because he is used to it. However, one who reviews a hundred and one times, puts work into the extra time he reviewed it, since he is not used to it, and therefore he is called 'one who works'. Because in order to be called the above name, one needs to do something which is a little extra, which he is not used to it, as one who awakens a new love to G-d through thinking about G-ds greatness, or at least to awaken his hidden love which every Jew has in his heart, and through it he will win over his desires, however, one who has no desires naturally, this love is not considered as work, and therefore he is called: 'one who does not work on himself for G-d, even though he only does good things and never does bad.