From the Islamic point of view, even though man can have private ownership rights to the wealth, however, Allah has clearly laid down the terms of trust. This is because, in Islam, all wealth belongs to Allah and human beings are only trustees to the wealth. On this point, Islam prescribes ways to carry out the trust so that a person has no right to use it to satisfy his whims. He has to observe the Divine commandments. If the violation is serious, hence, his inability to use his wealth properly provides the basis for the forfeiture of his right to his wealth. For those whom Allah has blessed with wealth, it is a test; and Muslims should strive to pass this test by not becoming worshipers of hoarded wealth.
Note:
The above is taken from below Source.
Please click to read full article:
http://arzim.blogspot.com/2010/02/all-wealth-belongs-to-god-and-man-is.html?m=1