Usury, when blights economy, spreads like cancer, and as doctor failed to cure cancer, men of intellect, politicians and economists fail to cure the plague of usury. What is astonishing is that some people believe that usury is good for people. In this, they are exactly like those who think that the body swelling that results form certain disease is a good sign for health while not every swelling in the body is a sign for health.
Cancer is an abnormal growth of cells in the body; a growth that is not in the benefit of the human being but rather it is devastating and killing. The same can be said about usury as all what results from it is not for the benefit of the society but it is very harmful to it. The problem is that the effects of usury do not appear in the structure of the society and economy all at once. Al-Razi said, “Although it appears that usury is increasing, it is in fact decreasing” and this is taken from the Qur’an in(Surat AL-Baqarah (The Cow), verse 176): (Allah makes usury to wane and makes almsgiving fruitful)
“Waning” means that something is gradually decreasing. This meaning is taken from the waning of the moon; as when the moon wanes, its size is gradually decreasing one night after another after being full. Those who are dealing through usury think that it is profitable while what the Omniscient and the All-knowing, and also reality, tells us is that usury causes any profit to wane and destroys economy as it afflicts economy with malignant diseases that could baffle the skilled physician. Usury is not a blessing and prosperity, but a chronic disease that takes away money and decreases it. The Prophet Muhammad (peace and blessing of Allah be upon him) said: “Thoughusury seems to be increasing, it is in fact turns towards decrease” Narrated by Ibn Mas’ud (may Allah be pleased with him); Ibn Majah transmitted it. Hadith No.2827 of Mishkat Al-Masabih.
Our Muslim scientists that knew the truths through Hadiths and Qur’an realized this fact. Al-Maraghi said: “usury results in havoc and ruin; as we see many people whose money was lost and families were broken up because they charge usury.” Al-Qasem said; “ there is no blessing in any money comes through usury because it is the result of violating divine laws. That is why its end is always fatal.” source:Imanway.com