Mishkat al-Masabih
Mishkat al-Masabih 4264
Arabic hadith text
وَعَنِ ابْنِ عَبَّاسٍ قَالَ نَهَى رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ عَن الشّرْب من قي السقاء
Translation
Ibn Abbas reported that the Messenger of Allah ﷺ forbade drinking directly from the mouth of a waterskin.