All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
This saying makes sense to a certain extent but it is not completely true. It is permissible for a Muslim to dispose of his wealth as long as he does not contradict the Sharee‘ah; that is to say by spending it on permissible matters without extravagance. One has the right to donate it – in full or in part – in case of his capacity to do so. It is better that this entails no harm to him or to his inheritors after him. Many Companions of the Prophet donated most of their wealth and some of them donated all their wealth. The Prophet, sallallaahu ‘alayhi wa sallam, approved these acts. Moreover, a Muslim may make a will regarding a portion of his wealth that does not exceed a third thereof even if this takes place in a state of serious illness by allocating a certain sum for specific people or charity organizations and endowment entities to be an ongoing charity for him whose reward does not stop increasing.
Concerning spending it on forbidden matters or giving it to entities that do not deserve it or spending it in what does not benefit him in the life of this world and in the hereafter, this constitutes wronging himself and entails that he commits sins because he deprives himself of the reward in the hereafter and of the benefit in the life of this world. Moreover, this constitutes wronging his inheritors, relatives and society.
Allaah Knows best.