He treated the financial director and he gave him some money
Question

                I work as a doctor in one of the hospitals and I treated a patient who is in charge of financial affairs. He gave me some money without me doing any work. Am I entitled to this money? Is it permissible for me to donate it to a charitable cause? Please note that I cannot return it.
Praise be to Allah.If this 
    money belongs to the state, then it is essential to know under what category 
    a person could obtain it, such as if it comes under the heading of helping 
    the needy, rewarding higly-skilled persons, and so on. If you fit the 
    description, then it is permissible for you to take the money, otherwise you 
    should give it to those who fit the description. If you cannot do that, then 
    spend it as needed for your work, and do not take any of it for yourself. 
This 
    director should fulfil the trust with which he has been charged, and not 
    give this money to anyone except those who are entitled to it. 
If you can 
    advise him concerning that, then this is what you must do, because the 
    Prophet  (peace and blessings of Allaah be upon him) said: “Help your 
    brother whether he is a wrongdoer or is wronged.” A man said: “O Messenger 
    of Allaah, I can help him if he is wronged but what if he is the wrongdoer, 
    how can I help him?” He said: “Stop him or prevent him from doing wrong. 
    That is how you help him.” Narrated by al-Bukhaari, 6952. 
If this 
    director is giving you this from his own money, then do not accept anything 
    from him, because that  comes under the heading of giving gifts to workers 
    that is forbidden in sharee’ah, because of the report narrated by 
    al-Bukhaari, 2597 and Muslim (1832) from Abu Humayd al-Saa’idi (may Allaah 
    be pleased with him), who said: The Prophet  (peace and blessings of 
    Allaah be upon him) appointed a man from al-Azd to be in charge of 
    collecting the zakaah, and when he came, he said: “This is for you and this 
    was given to me as a gift.” He (the Prophet  (peace and blessings of 
    Allaah be upon him)) said: “Why doesn’t he sit in the house of his father or 
    the house of his mother and see whether he is given anything or not? By the 
    One in Whose hand is my soul, none of you takes anything from it but he will 
    come carrying it on his neck on the Day of Resurrection, even if it is a 
    camel that is groaning or a cow that is mooing or a sheep that is bleating.” 
    Then he raised his hand until we could see the whiteness of his armpit and 
    said: “O Allaah, have I conveyed (the message)? O Allaah, have I conveyed 
    (the message)?” three times. 
According to 
    a version narrated by Muslim: Then he addressed us and praised and glorified 
    Allaah, then he said: “I appointed a man from among you to do this task 
    which Allaah has enjoined upon me, and he comes and says, ‘This is your 
    wealth and this is a gift that was given to me.’ Why doesn’t he sit in the 
    house of his father and mother so that gifts will be brought to him if he is telling the truth.” 
And Allaah knows best.