Musannaf Ibn Abi Shayba 13:2224

Abu Bakr narrated to us, he said: Waki’ narrated to us, he said: Al-A’mash narrated to us, from Khaythama, he said: Abu al-Darda’ said: "I was a merchant before the Prophet, may Allah bless him and grant him peace, was sent. When the Prophet, may Allah bless him and grant him peace, was sent, I wanted to combine trade and worship, but it did not work out for me. So, I abandoned trade and turned my attention to worship."