Kitaab-ul-Ijaarah [Book of Hiring] starts today.
Volume 3, Book 36, Number 461 :
Narrated by Abu Musa Al-Ashari (radiallaahu `anhu)
The Prophet (sallallaahu `alayhi wasallam) said, “The honest treasurer who gives willingly what he is ordered to give, is one of the two charitable persons, (the second being the owner).”
The treasurer who is put in charge of the wealth of a person here gives honestly whatever he’s ordered to give. So the reward of charity goes to the owner and to the caretaker as well. Why the reward? I’d say because it’s easy to make some slips here and there and get away with them. Being a treasurer is tempting, I’d assume.
Treasurer here can also be translated, in general meaning, as “employee”, or someone who is entrusted with a task that he needs to perform. Every person who does their job honestly and perfectly is a charitable person. So he gets the wage for his work and reward for being ‘charitable’.