Terry Crews isn't your average ex-athlete. When he left the NFL (he played defensive end and linebacker for three teams), he hadn't saved much of his football money. Soon, he was sweeping floors for $8 per hour, trying to get by while dreaming of an acting career.

After years of struggle and self-doubt, success finally revisited the versatile Crews. He has since excelled in TV commercials, TV shows, and movies. He's an author (of Manhood) and game show host (Who Wants to Be a Millionaire).

Crews was even in the group of people named "Time Magazine's Person of the Year in 2017" for bravely coming forth about his experiences with sexual assault. He's also an activist, a painter, a flutist, and designs high-end furniture. A Renaissance man with a rags-to-riches-to-rags-to riches backstory.

He recently talked to CNBC's Money Talks about his unique back and forth journey to far-reaching success and shared what he says was the absolute key to him achieving his potential. Four simple, powerful words. Something he decided about himself.

"You are already enough."

Crews recalled a time when his dad told him he'd never play in the NFL. After all, only one-in-a-million made it. Crews responded, "I'm that one-in-a-million. That's me." He went on to say:

"It hit me that the only way to make it was to think of yourself that way, as one in a million, because you truly are. People tend to think that that means someone else, but I was like, no, I choose to think that's me. And that changed everything."

He continued:

"My best advice is that you are already enough. Now, knowing that, go get it. You don't have to prove anything to anybody. You don't have to compete. You don't have to fight. Just be creative. But go now, do it now. Do not hesitate. And work on your endurance, work on the fact that you need to do it faster, better. And do it all day without being tired. But also know that you are enough. You're good. Now just go as far as you can. Every day. And you just keep getting farther and farther. And I'm telling you, you'll wake up. And you'll have made it. You will have made it."

What if you truly believed that you were enough?

For my book Find the Fire, I interviewed hypnotherapist Lisa Zaccheo. She told me something remarkable about the wide range of patients she has treated, for ailments ranging from overeating and extra-marital affairs to alcoholism and depression over not getting that promotion.

Amazingly, the root cause turns out to be the same for everyone she sees, regardless of their ailment. The same damning belief, the same root cause, in one form or another, keeps surfacing over, and over, and over again: "I'm not good enough."

Zaccheo says this belief is most often based on a misperception or a personal experience taken the wrong way. This belief has become an epidemic in the workplace: We beat ourselves up, project our "not good enough" onto others, and then they volley it right back. Everyone spirals down in a disempowering death spin.  

The point is that the first step in blazing your path to success is to stop telling yourself that you're not good enough. As Zaccheo told me: 

"'Not good enough' comes from differences--we think our differences are a curse instead of a blessing. We think our differences make us lesser than, but they make us greater than. We simply must get in touch with 'I'm good enough' and 'I'm meant to make a unique contribution.' You must believe that you are exceptional. You must believe you have the potential for your special kind of greatness, and that you're getting better each day."

The belief that I was enough was the underlying force that gave me the courage to leave corporate behind and pursue my dream of being an entrepreneur. It can work for you in your own personal renaissance.

You are already enough. Enough with the self-imposed limitations.