where to enter source for double entry

[Girard Aquino]

Hi. I am trying to pay off a debt we have with one of our family 
members. being an insurance agent, we bought a life insurance from him, 
and he was kind enough to credit 500 from his commission into our debt 
(not sure if i said that correctly - i mean he took off 500 from his 
commission and considered it payment from us for our debt). since 
gnucash always looks for a source for the money you transfer between 
accounts, where should I enter this amount as coming from? thank you.


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