Will you ever feel "old enough" ?

Sydney
My boyfriend and I are both 21. I want to get married sooo badly. Before we weren't getting married because he wanted to be financially ready. Now he has a real job working as a paramedic for an ambulance company. Now his reasoning for not being ready is that he doesn't feel old enough to be married. He said that he thought that by now he'd feel old enough but he doesn't. But we are 21, obviously we are old enough. Honestly I don't feel "old enough" either, but that doesn't stop me from wanting to be married.
 I truly think that you will never feel "old enough" and that's what I told him. Is that true? Do you ever feel "old enough"?