Musnad Ahmad 1158:1

Waki' narrated to us, Shu'bah narrated to us, from Qatadah, from Abu Ayyub al-Hajari, from Juwayriyah, that the Messenger of Allah (peace and blessings of Allah be upon him) entered upon Juwayriyah on a Friday while she was fasting. He said to her, "Did you fast yesterday?" She said, "No." He said, "Will you fast tomorrow?" She said, "No." He said, "Then break your fast."