The literal meaning of interest or Al-RIBA as it is used in the Arabic language means to excess or increase. In the Islamic terminology interest means effortless profit or that profit which comes free from compensation or that extra earning obtained that is free of exchange. Hazrat Shah Waliullah Dehlvi a great scholar and leader has given a very concise and precise definition of interest. He says,

"Riba` is a loan with the condition that the borrower will return to the lender more than and better than the quantity borrowed."

Interest is not a subject without trade and commerce. Islam recognises trade and commerce not only as a lawful profession but also as a moral duty. Islam has laid down a complete set of rules for trade. The reason for these rules is to specify what halal earning is. There are many traditions (Ahaadith) concerning halal provision that can also be found in the books containing the traditions of the prophet (peace be upon him). Actually, Islam has encouraged men to earn their own provision and to provide it to their families. The condition is that the earning has to be according to the conditions set by the Shari’ah. Any sort of transaction that does not correspond to the rules of trade will not be allowed. These rules can be found under the heading of trade in the books of jurisprudence. Interest is amongst those conditions which all dealings must be free from.
May God guide us on to the right path. Ameen

In verse 279 he says,

"If you do not, take notice of war from Allah and his Messenger sallallahu alaihe wasallm but if you repent you shall have your capital sum. Deal not unjustly and you shall not be dealt with unjustly."

In the second place in Surah Aal-Imran, verse no.130 Allah says,

"Oh you who believe! Devour not usury doubled and multiplied; but fear Allah that you may prosper."

Hazrat Jabir radiyallahu anhu has reported that the Messenger of Allah sallallahu alaihe wasallm cursed the devourer of usury, its payer, its scribe and its two witnesses. He also said that they were equal (in sin).