A good fighter has to be diligent and committed--doing what you hate to do but doing it like you love it, always testing yourself and forcing yourself to the limit. - Mike Tyson
The above quote jumped off the page at me. I think that there is such a powerful message in those deceptively simple words. This is a key toward growth in avodat HaShem - it's not enough to slog through something simply driven by the knowledge that it is "the right thing", despite the fact that we may not enjoy it. We must willingly try to make it into an enjoyable enterprise.
After reading that line, I was reminded of a famous story with Rav Moshe Feinstein OBM, told by a famed Rosh Yeshiva. This Rosh Yeshiva had spoken at a bar mitzvah where Rav Moshe was present as well. In the context of his speech, the Rosh Yeshiva admonished the bar mitzvah boy, trying to impress upon him the tremendous responsibility of fulfilling the mitzvot. He reminded the young man that "iz shver tzu* zein a Yid!" ("it's hard to be a Jew"), returning over and over to this theme.
Rav Moshe stood up and protested immediately after the Rosh Yeshiva concluded his speech. "Nein...iz nisht shver tzu zein a Yid - iz geshmak tzu zein a Yid!! Geshmak!" (No...it's not hard to be a Jew - it's a pleasure [roughly translated] to be a Jew! A pleasure!"
While Rav Moshe's intention was most likely to convey that ultimately the goodness and pleasure far outweighs any perceived difficulty associated with Judaism, I believe that we can take the message a step deeper based on the above idea. Even when it is difficult, it is imperative that we approach our tasks with the attitude that it is pleasurable, at the very least to be able to fully accomplish our goals. But in the end, this constant willfulness will bring about an actual change in our perspective as well...
* a big thanks to my good friend Steeeve for pointing out my grammatical error.