It gives value to what you give and to what you receive.
What are the merits of money?
The bible says at Eccl 7:12 "For wisdom is a protection just as money is a protection, but the advantage of knowledge is this: Wisdom preserves the life of its owner.
You can buy food, shelter, education, transportation, clothes and health care
It's a hell of a lot simpler than barter. And now, of course, we're moving into a post-money era for we have the benefit of EFT.
Money its great and the root of all evil