In the Quranic verse 35:29 Allah (swt) says:
“Surely they who recite the Book of Allah and keep up prayer and spend out of what We have given them secretly and openly, hope for a gain that will not perish’.
The words ‘Book of Allah’ mentioned in this verse refer to the Holy Quran. It means that the people who recite Quran punctually and who offer prayers (Salaah) with humility and submission and who spend in charity, such people are going to get great returns from their Creator. According to some of the Islamic scholars, the part of the verse ‘and spend of what we have given them secretly and openly’ refers to the Compulsory charity and the Voluntary charity because usually the former is given openly whereas the latter is not.
Giving donation for a good cause or offering Compulsory charity is a profitable bargain for the donor. This is because in the usual trade bargains, there is some amount of risk involved. There may be chances of profit as well as loss and even if the trader gets profit, it is within a limit. However, when a person spends for donation or charity out of the wealth given to him by Allah (swt), there is no risk involved. Though it may apparently seem that the deal is disadvantageous because of the money a person has to dole out in charity, but the truth is just the opposite. The money possessed by the wealthy actually belongs to Allah (swt) because the real ownership lies with Him whereas the wealthy people in the world are mere trustees. Allah (swt) has Commanded the rich to share their wealth with the underprivileged in order to avoid concentration of wealth in the hands of a few. This strategy is meant to create equality and justice in the society and to do away with starvation, poverty, deprivation, crimes etc. So we find that the Quranic rulings pertaining to charity provide a perfect solution for the upliftment of the downtrodden.
Therefore, those who try to ruin the plan of Allah (swt) by going against His Will and by becoming selfish and niggard then those people have to face the Wrath of Allah (swt). On the other hand, the people who obey their Creator and who willingly offer money for donation or charity, such people have been promised good returns from Allah (swt) in this life and the Hereafter. Allah (swt) not only promises to multiply their good deeds and offer them great returns but He also promises to protect them from all kinds of fear and grief. (2:277).