This is an amazing incident from the life of Ibn al-Mubarak (rahimahullah):
When knowledge really benefits its seeker…
Suwayd ibn Sa’id: ‘I saw ‘Abdullah ibn al-Mubarak in Makkah as he went to the (water of) zamzam and drank from it. Then he faced the Ka’bah and said,
‘O Allah, Ibn al-Mawali narrated to us from Muhammad ibn al-Munkadir, from Jabir from the Prophet (sallallahu `alayhi wa sallam) that he said, ‘The water of Zamzam is for whatever it’s drank for ‘ and here I am drinking it to prevent the thirst of the Day of Judgement.’ Then he drank it.