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.
ahmad:2647ʿAffān > Wuhayb > ʿAbdullāh b. Ṭāwus from his father

[Machine] "We used to say, as boys, that the one who returns to his vomit is like a dog. We did not know that the Messenger of Allah ﷺ had given an example of that until Ibn Abbas narrated to us that the Messenger of Allah ﷺ said, 'The one who returns to his vomit is like a dog.'"  

أحمد:٢٦٤٧حَدَّثَنَا عَفَّانُ حَدَّثَنَا وُهَيْبٌ حَدَّثَنَا عَبْدُ اللهِ بْنُ طَاوُسٍ عَنْ أَبِيهِ قَالَ

كُنَّا نَقُولُ وَنَحْنُ صِبْيَانٌ الْعَائِدُ فِي هِبَتِهِ كَالْكَلْبِ يَقِيءُ ثُمَّ يَعُودُ فِي قَيْئِهِ وَلَمْ نَعْلَمْ أَنَّ رَسُولَ اللهِ ﷺ ضَرَبَ فِي ذَلِكَ مَثَلًا حَتَّى حَدَّثَنَا ابْنُ عَبَّاسٍ أَنَّ رَسُولَ اللهِ ﷺ قَالَ الْعَائِدُ فِي هِبَتِهِ كَالْكَلْبِ يَقِيءُ ثُمَّ يَعُودُ فِي قَيْئِهِ