How does credit make the economy grow?

Having credit enable people to purchase items at a time they otherwise couldn't afford. For instance, if I can buy a car now on credit I am helping to employ people today who have had to get the raw materials, manufacture, transport and sell me the car. Additionally, I have to keep working to pay off the car and there are all those who finance the car and repossess it if I can't pay it off. Multiply that over thousands of consumers and the economy activity which means growth. If I have to save that money it may take me years to get that money together.