Re: Belief in Black magic
After the peace treaty of Hudaibiyah when the Holy Prophet (upon whom be peace) returned to Madinah, a deputation of the Jews of Khaibar visited Madinah in Muharram, A.H. 7 and met a famous magician, Labid bin Asam, who belonged to the Ansar tribe of Bani Zurayq. They said to him: “You know how Muhammad (upon whom be Allah’s peace and blessings) has treated us. We have tried our best to bewitch him but have not succeeded. Now we have come to you because you are a more skilled magician. Here are three gold coins, accept these and cast a powerful magic spell on Muhammad.”
In those days the Holy Prophet had a Jewish boy as his attendant. Through him they obtained a piece of the Holy Prophet’s comb with some hair stuck to it. Magic was worked on the same hair and the teeth of the comb. According to some traditions, magic was worked by Labid bin Asam himself, according to others, his sisters were more skilled than him and he got the spell cast through them. Whatever be the case, Labid placed this spell in the spathe of a male date-tree and his it under a stone at the bottom of Dharwan or Dhi Arwan, the well of Bani Zurayq. The spell took one whole year to have effect upon the Holy Prophet (upon whom be peace). In the latter half of the year the Holy Prophet started feeling as if was unwell. The last forty days became hard on him, of which the last three days were even harder. But its maximum effect on him was that he way melting away from within. He thought he had done a thing whereas, in fact, he had not done it: he thought he had visited his wives whereas he had not visited them; and sometimes he would doubt having seen something whereas, in fact, he had not seen it.
All these effects were confined to his own person; so much so that the other people could not notice what state he was passing through. As for his being a Prophet, no change occurred in the performance of his duties. There is no tradition to say that he might have forgotten some verses of the Qur’an in those days, or might have recited a verse wrongly, or a change might have occurred in the assemblies and in his counsels and sermons, or he might have presented a discourse as Revelation which may not have been revealed to him, or he might have missed a Prayer and thought that he had performed it. God forbid, if any such thing had happened, it would have caused a clamor and the whole of Arabia would have known that a magician had overpowered the one whom no power had been able to overpower. But the Holy Prophet’s position as a Prophet remained wholly unaffected by it. Only in his personal life he remained worried on account of it.
At last, one day when he was in the house of Hadrat Aishah, he prayed to Allah to be restored to full health. In the meantime he fell asleep or drowsed and on waking he said to Hadrat Aishah: “My Lord has told me what I had asked of Him.” Hadrat Aishah asked what it was. He replied: "Two men (i.e. two angels in human guise) came to me. One sat near my head and the other near my feet. The first asked: what has happened to him? The other replied: Magic has been worked on him. The first asked: who has worked it? He replied: Labid bin Asam. He asked: In what is it contained? He replied: In the comb and hair covered in the spathe of a male date-tree. He asked: where is it? He replied: under a stone at the bottom of Dhi Arwan (or Dharwan), the well of Bani Zurayq. He asked: what should be done about it? He replied: the well should be emptied and it should be taken out from under the stone. The Holy Prophet then sent Hadrat Ali, Hadrat Ammar bin Yasir and Hadrat Zubair: They were also joined by Jubair bin Iyas az-Zurqi (two men from Bani Zurayq). Later the Holy Prophet also arrived at the well along with some Companions. The water was taken out and the spathe recovered. There they found that beside the comb and hair there was a cord with eleven knots on it and a wax image with needles pricked into it. Gabriel (peace be on him) came and told him to repeat the Mu’awwidhatayn. As he repeated verse after verse, a knot was loosened and a needle taken out every time, till on finishing the last words all the knots were loosened and all the needles removed, and he was entirely freed from the charm. After this he called Labid and questioned him. He confessed his guilt and the Holy Prophet let him go, for he never avenged himself on anyone for any harm done to his person. He even declined to talk about it to others, saying that Allah had restored him to health; therefore he did not like that he should incite the people against anyone.
http://quranindepth.blogspot.co.uk/2010/11/effect-of-magic-on-prophet-muhammed.html