The Book of Prayers (Kitab Al-Salat) 
Muslim :: Book 4 : Hadith 1094
Mu'awiya b. al-Hakam said: While I was praying with the Messenger of Allah (may peace be upon him), a man in the company sneezed. I said: Allah have mercy on you! The people stared at me with disapproving looks, so I said: Woe be upon me, why is it that you stare at me? They began to strike their hands on their thighs, and when I saw them urging me to observe silence (I became angry) but I said nothing. When the Messenger of Allah (may peace be upon him) had said the prayer (and I declare that neither before him nor after him have I seen a leader who gave better instruction than he for whom I would give my father and mother as ransom). I swear that he did not scold, beat or revile me but said: Talking to persons is not fitting during the prayer, for it consists of glorifying Allah, declaring his Greatness. and recitation of the Qur'an or words to that effect. I said: Messenger of Allah. I was till recently a pagan, but Allah has brought Islam to us; among us there are men who have recourse to Kahins. He said, Do not have recourse to them. I said. There are men who take omens. That is something which they find in their breasts, but let it not turn their way (from freedom of action). I said: Among us there are men who draw lines. He said: There was a prophet who drew lines, so if they do it as they did, that is allowable. I had a maid-servant who tended goats by the side of Uhud and Jawwaniya. One day I happened to pass that way and found that a wolf had carried a goat from her flock. I am after all a man from the posterity of Adam. I felt sorry as they (human beings) feel sorry. So I slapped her. I came to the Messenger of Allah (may peace be upon him) and felt (this act of mine) as something grievous I said: Messenger of Allah, should I not grant her freedom? He (the Holy Prophet) said: Bring her to me. So I brought her to him. He said to her: Where is Allah? She said: He is in the heaven. He said: Who am I? She said: Thou art the Messenger of Allah. He said: Grant her freedom, she is a believing woman.