It is narrated from Hazrat Abu al-Muthanna Johani. He says: I was present with Hazrat Marwan bin Hakam when Hazrat Abu Saeed arrived. Marwan asked him, "Have you heard the Messenger of Allah (peace and blessings be upon him) forbidding blowing into a drinking vessel?" He replied, "Yes." The narrator says: Upon this, a man said, "I do not become fully quenched in one breath." Hazrat Abu Saeed said, "Separate the vessel from your mouth, then take a breath." The man said, "But what if I see something dirty (in the water)?" He replied, "Then pour out that water."