The son of adam who gives alms with his right hand while his left hand does not know more strongly than the whole creation of God. Charity with right hand and left hand do not know which means charity without expecting anything, without showing off, the intention is very clean and sincere only hope Allah SWT only. This is a great energy of charity.
There are still many people who can not do it, alms that do still contain elements of lust, the tendency to be praised, want to show off and want to get a reply from those who receive it. Such charity is not enough to give the energy of the giver or the receiver.