Hadith: A man went to the Prophet (may Allah's peace and blessings be upon him) as he made Zhihār against his wife yet had intercourse with her

عن ابن عباس: أن رجلا أتى النبي صلى الله عليه وسلم قد ظَاهَرَ مِنْ امرأته، فَوَقَعَ عليها، فقال: يا رسول الله، إني قد ظَاهَرْتُ مِنْ زَوْجَتِي، فَوَقَعْتُ عليها قَبْلَ أَنْ أُكَفِّرَ، فقال: «وما حَمَلَكَ على ذلك يرحمك الله؟»، قال: رَأَيْتُ خَلْخَالَهَا في ضوء القمر، قال: «فلا تَقْرَبْهَا حتى تَفْعَلَ ما أَمَرَكَ الله به».
[حسن] - [رواه أبو داود والترمذي والنسائي وابن ماجه]

Ibn ‘Abbās (may Allah be pleased with him) reported: A man, who made Zhihār (pre-islamic form of divorce) against his wife yet had intercourse with her, went to the Prophet (may Allah's peace and blessings be upon him). He said: "O Messenger of Allah, I uttered Zhihār against my wife, then I had intercourse with her before atoning." He said: "What caused you to do that, may Allah have mercy upon you?" He said: "I saw her anklet in the moonlight." The Prophet (may Allah's peace and blessings be upon him) said: "Then do not approach her (have intercourse with her) until you do what Allah has ordered you to do (the atonement for Zhihār)."
[Good hadith] - [Narrated by Ibn Majah - Narrated by At-Termedhy - An-Nasaa’i - Narrated by Abu Daoud]

Explanation

The Hadīth shows that this Companion was used to having intercourse with his wife so frequently. Being afraid that he would have sexual intercourse with her while fasting during Ramadan that had already started, he pronounced Zhihār against his wife. In other words, he likened her to a woman who is permanently prohibited for him to marry such as his mother, sister, aunt, etc. However, while she was serving him one night, he saw her anklet and was enticed into having intercourse with her, which he did. He later regretted this and went to the Prophet (may Allah's peace and blessings be upon him) asking about the ruling on what he did. The Prophet (may Allah's peace and blessings be upon him) ordered him not to touch his wife except after offering the expiation that Allah, the Exalted, has made obligatory for the one who made Zhihār against his wife. This Hadīth is a main reference on the issue of Zhihār.