7 I know you will rejoin that you possess nothing. Why, then, if you are so well prepared for battle, do you not take the field? Perhaps you think that you can wage war in your own country, although the Lord could do no signs in His? Why not? You ask. Take the answer which comes to you with his authority: “No prophet is accepted in his own country.” But, you will say, I do not seek honor; the approval of my conscience is enough for me. Neither did the Lord seek it; for when the multitudes would have made Him a king he fled from them. But where there is no honor there is contempt; and where there is contempt there is frequent rudeness; and where there is rudeness there is vexation; and where there is vexation there is no rest; and where there is no rest the mind is apt to be diverted from its purpose. Again, where, through restlessness, earnestness loses any of its force, it is lessened by what it loses, and that which is lessened cannot be called perfect. The upshot of all which is that a monk cannot be perfect in his own country. Now, not to aim at perfection is itself a sin.
Source: Letters (New Advent)