Al-Kāfi - Volume 7 > The Matters Permissible in Endowment, Charity, Gift, Present, Providing Conditional Housing and Matters Permissible or otherwise for a Child and others
Hadith #7

7- مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنْ عَلِيِّ بْنِ الْحَكَمِ عَنِ الْعَلاءِ بْنِ رَزِينٍ عَنْ مُحَمَّدِ بْنِ مُسْلِمٍ عَنْ أَبِي جَعْفَرٍ (عَلَيْهِ السَّلام) أَنَّهُ قَالَ فِي الرَّجُلِ يَتَصَدَّقُ عَلَى وُلْدٍ قَدْ أَدْرَكُوا إِذَا لَمْ يَقْبِضُوا حَتَّى يَمُوتَ فَهُوَ مِيرَاثٌ فَإِنْ تَصَدَّقَ عَلَى مَنْ لَمْ يُدْرِكْ مِنْ وُلْدِهِ فَهُوَ جَائِزٌ لأنَّ وَالِدَهُ هُوَ الَّذِي يَلِي أَمْرَهُ وَقَالَ لا يَرْجِعُ فِي الصَّدَقَةِ إِذَا ابْتَغَى بِهَا وَجْهَ اللهِ عَزَّ وَجَلَّ وَقَالَ الْهِبَةُ وَالنِّحْلَةُ يَرْجِعُ فِيهَا إِنْ شَاءَ حِيزَتْ أَوْ لَمْ تُحَزْ إِلا لِذِي رَحِمٍ فَإِنَّهُ لا يَرْجِعُ فِيهِ.

7. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from Ali ibn al-Hakam from al-‘Ala’ ibn Razin from Muhammad ibn Muslim who has narrated the following: “This is about the case of a man who gives charity to his grown up (mature) children. They do not take possession until he dies. Abu Ja’far, ‘Alayhi al-Salam, has said, ‘It remains as part of the legacy; but if he gives it as charity to his small children, then it (giving such charity) is permissible; their father is the one who is their guardian (in matters of taking possession for them). 5 He (the Imam) said, ‘The charity given for the sake of Allah, most Majestic, most Glorious, cannot be taken back.’ He (the Imam) said, ‘Gifts and grants can be taken back if one wants to do so, regardless, possession by the recipient has taken place or not, unless the recipient is a relative, in which case it cannot be taken back.’”