If Allah has blessed you with the ability to help or do good to someone, then don't waste even a moment wondering why I should do it.
Humans are the highest among all creatures, why should one become an animal for selfish reasons?
Allah has chosen you to help someone, otherwise it is not a big deal for Allah to bring someone else in your place and you end up needing help.
So be happy that Allah has created you as a medium to accept someone else's prayers.
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