كتاب الزكاة
12  
The Book of Zakat
(14)
Chapter: The virtue of spending and giving charity to relatives, spuses, children and parents, even if they are idolaters
(14)
باب فَضْلِ النَّفَقَةِ وَالصَّدَقَةِ عَلَى الْأَقْرَبِينَ وَالزَّوْجِ وَالْأَوْلَادِ وَالْوَالِدَيْنِ وَلَوْ كَانُوا مُشْرِكِينَ
Sahih Muslim 998 b

Anas reported that when this verse was tevealed:

" You will not attain righteousness till you give freely of what you love," Abu Talha said: I see that our Lord has demanded from us out of our property; so I make you a witness, Messenger of Allah. that I give my land known as Bairaha' for the sake of Allah. Upon this the Messenger of Allah (ﷺ) said: Give that to your relatives. So he gave it to Hassan b. Thabit and Ubayy b. Ka'b.
حَدَّثَنِي مُحَمَّدُ بْنُ حَاتِمٍ، حَدَّثَنَا بَهْزٌ، حَدَّثَنَا حَمَّادُ بْنُ سَلَمَةَ، حَدَّثَنَا ثَابِتٌ، عَنْ أَنَسٍ، قَالَ لَمَّا نَزَلَتْ هَذِهِ الآيَةُ ‏{‏ لَنْ تَنَالُوا الْبِرَّ حَتَّى تُنْفِقُوا مِمَّا تُحِبُّونَ‏}‏ قَالَ أَبُو طَلْحَةَ أُرَى رَبَّنَا يَسْأَلُنَا مِنْ أَمْوَالِنَا فَأُشْهِدُكَ يَا رَسُولَ اللَّهِ أَنِّي قَدْ جَعَلْتُ أَرْضِي بَرِيحَا لِلَّهِ ‏.‏ قَالَ فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ اجْعَلْهَا فِي قَرَابَتِكَ ‏"‏ ‏.‏ قَالَ فَجَعَلَهَا فِي حَسَّانَ بْنِ ثَابِتٍ وَأُبَىِّ بْنِ كَعْبٍ ‏.‏
Reference : Sahih Muslim 998b
In-book reference : Book 12, Hadith 53
USC-MSA web (English) reference : Book 5, Hadith 2186
  (deprecated numbering scheme)