Hamzah bin Abdullah narrates from his father (Sayyiduna Abdullah bin Umar, may Allah be pleased with them both) that the Prophet Muhammad (peace and blessings be upon him) said: "Once I was asleep and I saw in a dream that a bowl was brought to me in which there was milk. I drank from it until I felt its nourishment flowing in my fingernails. Then I gave the remaining milk to Umar bin Khattab." The people asked: What interpretation did you give to this? The Prophet Muhammad (peace and blessings be upon him) said: "Knowledge."