Ruling on a guarantor taking money in exchange for his guarantee

Question:
The first message in this episode is from a listener (A. M.) from Al-Layf, who sent it and says: One of my acquaintances went to a car showroom to buy a car on installment. They asked him for a guarantor who is in debt, so he asked me to guarantee for him. I agreed, and we went to the showroom. After I provided the required guarantee, the man gave me a sum of one thousand Saudi riyals without me asking for it. Is this amount lawful for me, or should I return it to him? I ask for your guidance. May Allah reward you with good.

Answer:
In the name of Allah, the Most Gracious, the Most Merciful. Praise be to Allah, and may Allah send blessings and peace upon the Messenger of Allah, upon his family and his Companions, and upon those who follow his guidance. As for what follows:
You must return this amount to its owner; because it is in exchange for your guarantee for him, which is a guarantee of debt, meaning that you pay it on his behalf if the need arises, with this increase that he gave you in advance. A guarantor does not take anything for his guarantee; because it is considered a voluntary act and assistance to his brother, and it is not something for which compensation is exchanged. Therefore, it is obligatory for you to return it to him, to return this amount to its owner. Yes.

The presenter : May Allah reward you with good.