Sahih Muslim Book 10, Hadith Number 3852.

Chapter : He (the Holy Prophet) cursed the one who accepts interest and the one who pays it.

Abil Qiliba reported: I was in Syria (having) a circle (of friends) in which was Muslim b. Yasir. There came Abu’l-Ash’ath. He (the narrator) said that they (the friends) called him: Abu’l-Ash’ath, Abu’l-Ash’ath, and he sat down. I said to him: Narrate to our brother the hadith of Ubada b. Samit. He said: Yes. We went out on an expedition, Mu’awiya being the leader of the people, and we gained a lot of spoils of war. And there was one silver utensil in what we took as spoils. Mu’awiya ordered a person to sell it for payment to the people (soldiers). The people made haste in getting that. The news of (this state of affairs) reached ‘Ubada b. Samit, and he stood up and said: I heard Allah’s Messenger (may peace be upon him) forbidding the sale of gold by gold, and silver by silver, and wheat by wheat, and barley by barley, and dates by dates, and salt by salt, except like for like and equal for equal. So he who made an addition or who accepted an addition (committed the sin of taking) interest. So the people returned what they had got. This reached Mu’awiya. and he stood up to deliver an address. He said: What is the matter with people that they narrate from the Messenger (may peace be upon him) such tradition which we did not hear though we saw him (the Holy Prophet) and lived in his company? Thereupon, Ubida b. Samit stood up and repeated that narration, and then said: We will definitely narrate what we heard from Allah’s Messenger (may peace be upon him) though it may be unpleasant to Mu’awiya (or he said: Even if it is against his will). I do not mind if I do not remain in his troop in the dark night. Hammad said this or something like this.