Why is private property a source of economic growth?It is for Macroeconomics

I would say that private property is a source of economic
growth because people who have (or are allowed to have) private property want to get
more of it.

In a free market economy, the desire for
property (and money) is one of the major drivers or economic growth.  People will try to
create new products and new ways of making products so that they will be able to get
more money.  This allows the economy to grow as people come up with new things to make
and better ways to make things.

So private property gives
people a powerful motive to work hard and that often leads to economic
growth.

For a more detailed statement of this idea, read
the first few paragraphs of the paper that I have linked to
below.