The prophet ﷺ passed by Ibn Sa’Id along with some of his companions. ‘Umar b. al-Kattab was among them. He was playing with boys near the fortress of Banu Maghalah. He was near the age of puberty (i.e. a boy). Before he was aware, the Messenger of Allah ﷺ gave him a pat on the back and said : Do you testify that you are the Messenger of Allah Ibn Sayyad then looked at him and said: I testify that you are the Apostle of Gentiles. Ibn Sayyad then said the prophet ﷺ then asked him : What comes to you ? He replied: One who speaks the truth and one who lies come to me. The prophet (may peace upon him) said: You are confused. The Messenger of Allah (may peace upon him) said to him: I have concealed something (in my hand) and he concealed the verse “the day when the sky will bring forth smoke (dukhan) clearly visible Ibn Sayyad said: It is smoke (dukhan) .The Messenger of Allah ﷺ said: Away with you, You cannot get farther than your rank. ‘Umar said: “Messenger of Allah, permit me to cut off his head. The Messenger of Allah ﷺ said: If he is the one (the Dajjal), you will not be given power over him, and if he is not, you will not do well in killing him.  

أَنَّ النَّبِيَّ ﷺ مَرَّ بِابْنِ صَائِدٍ فِي نَفَرٍ مِنْ أَصْحَابِهِ فِيهِمْ عُمَرُ بْنُ الْخَطَّابِ وَهُوَ يَلْعَبُ مَعَ الْغِلْمَانِ عِنْدَ أُطُمِ بَنِي مَغَالَةَ وَهُوَ غُلاَمٌ فَلَمْ يَشْعُرْ حَتَّى ضَرَبَ رَسُولُ اللَّهِ ﷺ ظَهْرَهُ بِيَدِهِ ثُمَّ قَالَ أَتَشْهَدُ أَنِّي رَسُولُ اللَّهِ قَالَ فَنَظَرَ إِلَيْهِ ابْنُ صَيَّادٍ فَقَالَ أَشْهَدُ أَنَّكَ رَسُولُ الأُمِّيِّينَ ثُمَّ قَالَ ابْنُ صَيَّادٍ لِلنَّبِيِّ ﷺ أَتَشْهَدُ أَنِّي رَسُولُ اللَّهِ فَقَالَ لَهُ النَّبِيُّ ﷺ آمَنْتُ بِاللَّهِ وَرُسُلِهِ ثُمَّ قَالَ لَهُ النَّبِيُّ ﷺ مَا يَأْتِيكَ قَالَ يَأْتِينِي صَادِقٌ وَكَاذِبٌ فَقَالَ لَهُ النَّبِيُّ ﷺ خُلِّطَ عَلَيْكَ الأَمْرُ ثُمَّ قَالَ رَسُولُ اللَّهِ ﷺ إِنِّي قَدْ خَبَّأْتُ لَكَ خَبِيئَةً وَخَبَّأَ لَهُ { يَوْمَ تَأْتِي السَّمَاءُ بِدُخَانٍ مُبِينٍ } قَالَ ابْنُ صَيَّادٍ هُوَ الدُّخُّ فَقَالَ رَسُولُ اللَّهِ ﷺ اخْسَأْ فَلَنْ تَعْدُوَ قَدْرَكَ فَقَالَ عُمَرُ يَا رَسُولَ اللَّهِ ائْذَنْ لِي فَأَضْرِبَ عُنُقَهُ فَقَالَ رَسُولُ اللَّهِ ﷺ إِنْ يَكُنْ فَلَنْ تُسَلَّطَ عَلَيْهِ يَعْنِي الدَّجَّالَ وَإِلاَّ يَكُنْ هُوَ فَلاَ خَيْرَ فِي قَتْلِهِ  

Nafi' told that Ibn Umar used to say: I swear by Allah that I do not doubt that Antichrist is Ibn Sayyad.  

أَنَّ الْمَسِيحَ الدَّجَّالَ ابْنُ صَيَّادٍ  

You swear by Allah! He said: I heard Umar swearing to that in the presence of the Messenger of Allah ﷺ, but the Messenger of Allah ﷺ did not make any objection to it.  

سَمِعْتُ عُمَرَ يَحْلِفُ عَلَى ذَلِكَ عِنْدَ رَسُولِ اللَّهِ ﷺ فَلَمْ يُنْكِرْهُ رَسُولُ اللَّهِ ﷺ  

We saw the last of Ibn Sayyad at the battle of the Harrah.  

فَقَدْنَا ابْنَ صَيَّادٍ يَوْمَ الْحَرَّةِ  

The Prophet ﷺ said: The Last Hour will not come before there come forth thirty Dajjals (fraudulents), everyone presuming himself that he is an apostle of Allah.  

قَالَ رَسُولُ اللَّهِ ﷺ لاَ تَقُومُ السَّاعَةُ حَتَّى يَخْرُجَ ثَلاَثُونَ دَجَّالُونَ كُلُّهُمْ يَزْعُمُ أَنَّهُ رَسُولُ اللَّهِ  

The Prophet ﷺ said: The Last Hour will not come before there come forth thirty liar Dajjals (fraudulents) lying on Allah and His Apostle.  

قَالَ رَسُولُ اللَّهِ ﷺ لاَ تَقُومُ السَّاعَةُ حَتَّى يَخْرُجَ ثَلاَثُونَ كَذَّابًا دَجَّالاً كُلُّهُمْ يَكْذِبُ عَلَى اللَّهِ وَعَلَى رَسُولِهِ  

Do you think that his one of them, that is al-Mukhtar (al-Thaqaff)? He said : He is from the leaders.  

فَذَكَرَ نَحْوَهُ فَقُلْتُ لَهُ أَتَرَى هَذَا مِنْهُمْ يَعْنِي الْمُخْتَارَ فَقَالَ عَبِيدَةُ أَمَا إِنَّهُ مِنَ الرُّءُوسِ