It is narrated from Sayyiduna Ibn Mas'ud (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "The curse of Allah is upon the one who consumes usury, the one who gives it, the one who witnesses it, and the one who records it." Also, "When usury and adultery become prevalent in a people, they make Allah's punishment lawful upon themselves."
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 3809