Allah's Statement: "They ask your legal instruction concerning women, say: Allah instructs you about them, and about what is recited unto you in the Book concerning orphan girls.. ." (V.4:127) Sahih al-Bukhari 4600

Arabic hadith text
حَدَّثَنَا عُبَيْدُ بْنُ إِسْمَاعِيلَ، حَدَّثَنَا أَبُو أُسَامَةَ، قَالَ : حَدَّثَنَا هِشَامُ بْنُ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ ‏‏{‏وَيَسْتَفْتُونَكَ فِي النِّسَاءِ قُلِ اللَّهُ يُفْتِيكُمْ فِيهِنَّ‏}‏ إِلَى قَوْلِهِ ‏‏{‏وَتَرْغَبُونَ أَنْ تَنْكِحُوهُنَّ‏}‏‏.‏ قَالَتْهُوَ الرَّجُلُ تَكُونُ عِنْدَهُ الْيَتِيمَةُ، هُوَ وَلِيُّهَا وَوَارِثُهَا، فَأَشْرَكَتْهُ فِي مَالِهِ حَتَّى فِي الْعِذْقِ، فَيَرْغَبُ أَنْ يَنْكِحَهَا، وَيَكْرَهُ أَنْ يُزَوِّجَهَا رَجُلاً، فَيَشْرَكُهُ فِي مَالِهِ بِمَا شَرِكَتْهُ فَيَعْضُلَهَا فَنَزَلَتْ هَذِهِ الآيَةُ‏.‏
Translation
Narrated `Aisha

Regarding the Verse:--"They ask your instruction concerning the women. Say: Allah instructs you about them and yet whom you desire to marry." (4.127) (has been revealed regarding the case of) a man who has an orphan girl, and he is her guardian and her heir. The girl shares with him all his property, even a date-palm (garden), but he desires to marry her and dislikes to give her in marriage to somebody else who would share with him the property she is sharing with him, and for this reason that guardian prevents that orphan girl from marrying. So, this Verse was revealed.