Do not those who always seek consolation deserve to be called mercenaries? Do not those who always think of their own profit and gain prove that they love themselves rather than Christ? Where can a man be found who desires to serve God for nothing? Rarely indeed is a man so spiritual as to strip himself of all things. And who shall find a man so truly poor in spirit as to be free from every creature? His value is like that of things brought from the most distant lands.
If a man give all his wealth, it is nothing; if he do great penance, it is little; if he gain all knowledge, he is still far afield; if he have great virtue and much ardent devotion, he still lacks a great deal, and especially, the one thing that is most necessary to him. What is this one thing? That leaving all, he forsake himself, completely renounce himself, and give up all private affections. Then, when he has done all that he knows ought to be done, let him consider it as nothing, let him make little of what may be considered great; let him in all honesty call himself an unprofitable servant. For truth itself has said: "When you shall have done all these things that are commanded you, say: we are unprofitable servants.'" 
Then he will be truly poor and stripped in spirit, and with the prophet may say: "I am alone and poor."  No one, however, is more wealthy than such a man; no one is more powerful, no one freer than he who knows how to leave all things and think of himself as the least of all.
 Luke 17:10.  Ps. 24:16.
 Ps. 24:16.