(6) باب الْعَمَلِ الَّذِي يُبْتَغَى بِهِ وَجْهُ اللَّهِ
Narrated Mahmud bin Ar-Rabi'a:
I remember that the Allah's Messenger (ﷺ) took water from a bucket (which was in our home used for getting water out of well) with his mouth (and threw it on my face).
Reference: Sahih al-Bukhari 6422
In-book reference: Book 81, Hadith 11
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 1, Book 76, Hadith 430