Musnad Ahmad 31:866

Isma'il narrated to us, Ali ibn al-Mubarak narrated to me, and Rawh narrated to us, Husayn al-Mu'allim narrated to us, Yahya ibn Abi Kathir narrated to us, Abu Sa'id, the freed slave of al-Mahri, narrated to me, from Abu Sa'id al-Khudri, that the Messenger of Allah (may Allah bless him and grant him peace) sent an expedition to Banu Lihyan of Banu Hudhayl—Rawh said: "from Hudhayl"—he said: "Let one out of every two men go forth, and the reward is between them." Then the Messenger of Allah (may Allah bless him and grant him peace) said: "O Allah, bless for us our mudd and our sa', and grant us two blessings along with the blessing."