It means that before a person dies they should give their money away to their children or to some kind of charity. It is their way of leaving this earth a better place for others. it is like leaving a legacy. However, a greedy man will somehow think they are going to take it with them and all that they will insure is a lot of bickering and fighting amongst those left as to who gets what. And the rich man will be all but forgotten except for the anger and bitterness that will be left behind.
Hope this helps.