Musnad Ahmad 32:1193

Ibn Abi ‘Adi narrated to us, from Humayd, from Anas, who said: "The prayer was established, and there was something between the Prophet, peace and blessings of Allah be upon him, and his wives, so he began to turn some of them away from others." Then Abu Bakr came and said: "Stuff their mouths with dirt, O Messenger of Allah, and go out to the prayer."