Sahih Bukhari Volume 2, Book 24, Hadith 1426

حَدَّثَنَا عُثْمَانُ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا جَرِيرٌ، عَنْ مَنْصُورٍ، عَنْ شَقِيقٍ، عَنْ مَسْرُوقٍ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ إِذَا أَنْفَقَتِ الْمَرْأَةُ مِنْ طَعَامِ بَيْتِهَا غَيْرَ مُفْسِدَةٍ كَانَ لَهَا أَجْرُهَا بِمَا أَنْفَقَتْ وَلِزَوْجِهَا أَجْرُهُ بِمَا كَسَبَ، وَلِلْخَازِنِ مِثْلُ ذَلِكَ، لاَ يَنْقُصُ بَعْضُهُمْ أَجْرَ بَعْضٍ شَيْئًا ‏"‏‏

Narrated By 'Aisha : Allah's Apostle said, "When a woman gives in charity some of the foodstuff (which she has in her house) without spoiling it, she will receive the reward for what she has spent, and her husband will receive the reward because of his earning, and the storekeeper will also have a reward similar to it. The reward of one will not decrease the reward of the others."