Abu Dawud Book 33, Hadith Number 4443.

Narated By An-Nu’man ibn Bashir : Habib ibn Salim said: A man called AbdurRahman ibn Hunayn had intercourse with his wife’s slave-girl. The matter was brought to an-Nu’man ibn Bashir who was the Governor of Kufah. He said: I shall decide between you in accordance with the decision of the Apostle of Allah (PBUH). If she made her lawful for you, I shall flog you one hundred lashes. If she did not make her lawful for you, I shall stone you to death. So they found that she had made her lawful for him. He, therefore, flogged him one hundred lashes.