Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) said: A man came to the Prophet (peace and blessings be upon him) and said: "O Messenger of Allah, I pronounced zihar on my wife, and then I was intimate with her before offering the expiation." He (peace and blessings be upon him) said: "What led you to do that?" He said: "I saw her shin in the moonlight, so I went to her." The Messenger of Allah (peace and blessings be upon him) said: "Keep away from her until you have offered the expiation."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 11549