Abu Qatadah (May Allah be pleased with him) reported:
Messenger of Allah (ﷺ) said, "He who serves others with drinking water should be the last to drink himself."[At-Tirmidhi]. (ES)
App reference (ES): Book 3, Hadith 46 (ES)
Arabic/English book reference (ES): Book 3, Hadith 773 (ES)