مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3702
Musnad of Abdullah bin Mas'ood
It was narrated from 'Abdullah bin Mas'ood (رضي الله عنه) that he said: Two deals in one are not valid. The Messenger of Allah (ﷺ) said: "May Allah curse the one who consumes riba, the one who pays it, the one who witnesses it and the one who writes it down."
Musnad Ahmad 3725Saheeh, because of corroborating evidence, Muslim (1597) and