Sahih Muslim 2146 a
'Urwa b. Zubair and Fatima daughter of Mandhir b. Zubair, reported that Asma' daughter of Abu Bakr was at the time of migration in the family way with 'Abdullah b. Zubair (in her womb). She came to Quba' and gave birth to 'Abdullah at that place and then sent him to Allah's Messenger (ﷺ) so that he should rub his palate with chewed dates. Allah's Messenger (may peace he upon him) took hold of him (the child) and he placed him in his lap and then called for dates. 'A'isha said:
Some time was spent before we were able to find them. He (the Holy Prophet) chewed them and then put his saliva in his mouth. The first thing that entered his stomach, was the saliva of Allah's Messenger (ﷺ). Asma' said: He then rubbed him and blessed him and gave him the name of Abdullah. He ('Abdullah) went to him (the Holy Prophet) when he had attained the age of seven or eight years in order to pledge allegiance to Allah's Messenger (ﷺ) as Zubair had commanded him to do. Allah's Messenger (ﷺ) smiled when he saw him coming towards him and then accepted his allegiance.
حَدَّثَنَا الْحَكَمُ بْنُ مُوسَى أَبُو صَالِحٍ، حَدَّثَنَا شُعَيْبٌ، - يَعْنِي ابْنَ إِسْحَاقَ - أَخْبَرَنِي 
 هِشَامُ بْنُ عُرْوَةَ، حَدَّثَنِي عُرْوَةُ بْنُ الزُّبَيْرِ، وَفَاطِمَةُ بِنْتُ الْمُنْذِرِ بْنِ الزُّبَيْرِ، أَنَّهُمَا قَالاَ خَرَجَتْ
 أَسْمَاءُ بِنْتُ أَبِي بَكْرٍ حِينَ هَاجَرَتْ وَهِيَ حُبْلَى بِعَبْدِ اللَّهِ بْنِ الزُّبَيْرِ فَقَدِمَتْ قُبَاءً فَنُفِسَتْ
 بِعَبْدِ اللَّهِ بِقُبَاءٍ ثُمَّ خَرَجَتْ حِينَ نُفِسَتْ إِلَى رَسُولِ اللَّهِ صلى الله عليه وسلم لِيُحَنِّكَهُ فَأَخَذَهُ
 رَسُولُ اللَّهِ صلى الله عليه وسلم مِنْهَا فَوَضَعَهُ فِي حَجْرِهِ ثُمَّ دَعَا بِتَمْرَةٍ قَالَ قَالَتْ عَائِشَةُ
 فَمَكَثْنَا سَاعَةً نَلْتَمِسُهَا قَبْلَ أَنْ نَجِدَهَا فَمَضَغَهَا ثُمَّ بَصَقَهَا فِي فِيهِ فَإِنَّ أَوَّلَ شَىْءٍ دَخَلَ
 بَطْنَهُ لَرِيقُ رَسُولِ اللَّهِ صلى الله عليه وسلم ثُمَّ قَالَتْ أَسْمَاءُ ثُمَّ مَسَحَهُ وَصَلَّى عَلَيْهِ وَسَمَّاهُ
 عَبْدَ اللَّهِ ثُمَّ جَاءَ وَهُوَ ابْنُ سَبْعِ سِنِينَ أَوْ ثَمَانٍ لِيُبَايِعَ رَسُولَ اللَّهِ صلى الله عليه وسلم
 وَأَمَرَهُ بِذَلِكَ الزُّبَيْرُ فَتَبَسَّمَ رَسُولُ اللَّهِ صلى الله عليه وسلم حِينَ رَآهُ مُقْبِلاً إِلَيْهِ ثُمَّ بَايَعَهُ
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