The greatest sin is being ungrateful. I truly believe this. Those who have no real involvement with anyone other than themselves are guilty of this sin frequently. They are helped to find a job, lent money, taken to the doctor, endless varieties of being helped along through life. They never feel grateful and never say thanks. And they wonder why they are not helped again. Sometimes someone you have helped very little will never forget and be very grateful. Which is great. Which is just to say, if you help someone don’t expect to be thanked. You did it for the good of yourself.