Hadith 344
Chapter 21: At the beginning of Islam, intercourse did not necessitate ghusl unless semen was emitted, then that was abrogated and ghusl becomes obligatory for intercourse - كتاب الحيض
حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُعَاذٍ الْعَنْبَرِيُّ، حَدَّثَنَا الْمُعْتَمِرُ، حَدَّثَنَا أَبِي، حَدَّثَنَا أَبُو الْعَلاَءِ بْنُ الشِّخِّيرِ، قَالَ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَنْسَخُ حَدِيثُهُ بَعْضُهُ بَعْضًا كَمَا يَنْسَخُ الْقُرْآنُ بَعْضُهُ بَعْضًا .
Abu al. 'Ala' b. al-Shikhkhir said:
The Messenger of Allah (ﷺ) abrogated some of his commands by others, just as the Qur'an abrogates some part with the other.
Reference : Sahih Muslim 344
In-book reference : Book 3, Hadith 99
USC-MSA web (English) reference : Book 3, Hadith 675