To be a generosity man

I Samuel 25:1-20
Time:Samuel was passed away. David went to the desert of Mon.
A certain man in Mon who has property there at Carmel. His name was Nabal, ad his wife's name is Abigil, She was an intelligent and beautiful woman.
David said "Nabal has paid me back evil for good. May God deal with David, be it ever so severly, if by morning I leave alive one male of all who belong to him"
David requested Nabal is not unreasonable. He is not demanding protection money, but asking some return on past services. After all, the man was rich and it was sheep shearing, a feast time.
Abigail is as clever as she is beautiful. Her quick action saves the lives of her husband and household. She evidently made a good impression on David.
The writer sees Nabel's death of a double stroke as God's punishment.
My Load, let the blame be on me alone. Please forgive your servant's offense, for the Load will certainly make a lasting dynasty for my master. because he flights the Load's battle. Let no wrongdoing be found in you as long as you live.  
Why?
David haven't be a king, and Samuel is dead, not prophet existed.
David requested in reasonable, for David's men took care Nabal's property,  David did a good things but returned evil, so he was angry.
Beautiful and cleaver woman is good couple, so David like Abigil, left good image in David.
How?
Cleaver usually does not connect with beauty, if beauty plus cleaver is best one. Don't be a food man like Nabal, wicked man, no one can talk to him, and stun, selfish man. How about me? Sometime I am selfish, I have to more generosity.