Narrated 'Abdullah bin 'Umar:
'Umar bin Al-Khattab set out with Allah's Apostle, and a group of his companions to Ibn Saiyad. They found him playing with the boys in the fort or near the Hillocks of Bani Maghala. Ibn Saiyad was nearing his puberty at that time, and he did not notice the arrival of the Prophet till Allah's Apostle stroked him on the back with his hand and said, "Do you testify that I am Allah's Apostle?" Ibn Saiyad looked at him and said, "I testify that you are the Apostle of the unlettered ones (illiterates)". Then Ibn Saiyad said to the Prophets . "Do you testify that I am Allah's Apostle?" The Prophet denied that, saying, "I believe in Allah and all His Apostles," and then said to Ibn Saiyad, "What do you see?" Ibn Saiyad said, "True people and liars visit me." The Prophet said, "You have been confused as to this matter." Allah's Apostle added, "I have kept something for you (in my mind)." Ibn Saiyad said, "Ad-Dukh." The Prophet said, "Ikhsa (you should be ashamed) for you can not cross your limits." 'Umar said, "O Allah's Apostle! Allow me to chop off h is neck." Allah's Apostle said (to Umar). "Should this person be him (i.e. Ad-Dajjal) then you cannot over-power him; and should he be someone else, then it will be no use your killing him." 'Abdullah bin 'Umar added: Later on Allah's Apostle and Ubai bin Ka'b Al-Ansari (once again) went to the garden in which Ibn Saiyad was present.
When Allah's Apostle entered the garden, he started hiding behind the trunks of the date-palms intending to hear something from Ibn Saiyad before the latter could see him. Ibn Saiyad was Lying on his bed, covered with a velvet sheet from where his mumur were heard. Ibn Saiyad's mother saw the Prophet and said, "O Saf (the nickname of Ibn Saiyad)! Here is Muhammad!" Ibn Saiyad stopped his murmuring. The Prophet said, "If his mother had kept quiet, then I would have learnt more about him." 'Abdullah added: Allah's Apostle stood up before the people (delivering a sermon), and after praising and glorifying Allah as He deserved, he mentioned the Ad-Dajjal saying, "I warn you against him, and there has been no prophet but warned his followers against him. Noah warned his followers against him but I am telling you about him, something which no prophet has told his people of, and that is: Know that he is blind in one eye where as Allah is not so."