Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
malik:18-33Yaḥyá > Mālik > Nāfiʿ > ʿAbdullāh b. ʿUmar

Yahya related to me from Malik from Nafi that Abdullah ibn Umar used to be cupped while he was fasting. Nafi said, "He later stopped doing that, and would not be cupped when he was fasting until he had broken the fast."  

مالك:١٨-٣٣حَدَّثَنِي يَحْيَى عَنْ مَالِكٍ عَنْ نَافِعٍ عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ

أَنَّهُ كَانَ يَحْتَجِمُ وَهُوَ صَائِمٌ قَالَ ثُمَّ تَرَكَ ذَلِكَ بَعْدُ فَكَانَ إِذَا صَامَ لَمْ يَحْتَجِمْ حَتَّى يُفْطِرَ