Sahih al-Bukhari 5077
Narrated `Aisha:
I said, "O Allah's Messenger (ﷺ)! Suppose you landed in a valley where there is a tree of which something 
has been eaten and then you found trees of which nothing has been eaten, of which tree would you let 
your camel graze?" He said, "(I will let my camel graze) of the one of which nothing has been eaten 
before." (The sub-narrator added: `Aisha meant that Allah's Messenger (ﷺ) had not married a virgin besides 
herself .)
حَدَّثَنَا إِسْمَاعِيلُ بْنُ عَبْدِ اللَّهِ، قَالَ حَدَّثَنِي أَخِي، عَنْ سُلَيْمَانَ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ قُلْتُ يَا رَسُولَ اللَّهِ أَرَأَيْتَ لَوْ نَزَلْتَ وَادِيًا وَفِيهِ شَجَرَةٌ قَدْ أُكِلَ مِنْهَا، وَوَجَدْتَ شَجَرًا لَمْ يُؤْكَلْ مِنْهَا، فِي أَيِّهَا كُنْتَ تُرْتِعُ بَعِيرَكَ قَالَ ‏
"‏ فِي الَّذِي لَمْ يُرْتَعْ مِنْهَا ‏"‏‏.‏ تَعْنِي أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم لَمْ يَتَزَوَّجْ بِكْرًا غَيْرَهَا‏.‏