you what you intend ya Yazid , and to you what took ya Maan] لك ما نويت يا يزيد ولك ما أخذت يا معن

5 - وعن أبي يزيد معن بن يزيد بن الأخنس رضي الله عنهم وهو وأبوه وجده صحابيون قال : كان أبي يزيد أخرج دنانير يتصدق بها فوضعها عند رجل في المسجد فجئت فأخذتها فأتيته بها فقال : والله ما إياك أردت فخاصمته إلى رسول الله صلى الله عليه و سلم فقال : [ لك ما نويت يا يزيد ولك ما أخذت يا معن ] رواه البخاري.
5- Ma`n bin Yazid bin Akhnas (May Allah be pleased with them) (he, his father and his grandfather, all were Companions) reported: My father set aside some dinars for charity and gave them to a man in the mosque. I went to that man and took back those dinars. He said: "I had not intended you to be given.'' So we went to Messenger of Allah (PBUH), and put forth the matter before him. He said to my father, "Yazid, you have been rewarded for what you intended.'' And he said to me, "Ma`n, you are entitled to what you have taken.''
[Al-Bukhari].

Commentary:
1- This Hadith leads us to the conclusion that if Sadaqah (charity), goes to a needy son of a Muslim, there is no need to take it back from him for the reason that the father had intended to give it to a deserving person. The former gets the reward for it on account of his Niyyah (intention). This however, will be reckoned as Nafli Sadaqah (voluntary charity) because the obligatory Zakat (Sadaqah) cannot be given to the donor's own dependents.
2- It is permissible in Shari`ah to make someone a Wakil (attorney or agent) for Sadaqah.
3- It does not amount to disobedience on the part of a son to take his father to a competent authority or scholar to know the legal position on any issue, in the same way, as mutual discussion and debate on matters of Shari`ah does not amount to insolence. (Fath Al-Bari, chapter on Zakat). .