Will Smith on marriage

Will Smith has a simple rule for a long lasting marriage.  Don’t quit.

Smith spoke ET, while walking the red carpet for Concussion.

“We’ve been married 20 years and we’ve been asking ourselves [what’s the secret to marriage] and really at the end of the day it’s just not quitting,” the 47-year-old actor said of Pinkett Smith, who he first started dating in 1995 and then married two years later. “You can’t expect it to be easy, it’s like our marriage was the most difficult, grueling, excruciating thing that we have ever taken on in our lives. And you know were just not quitters.”

“If there is a secret I would say is that we never went into working in our relationship,” he continued. “We only ever worked on ourselves individually, and then presented ourselves to one another better than we were previously.”

Romantic: The Oscar nominee has taken to Facebook to refute divorce rumors as well as share sweet posts for his wife Jada, such as a birthday message that included this throwback photo 'taken at your mom's house 20 years ago'

Romantic: The Oscar nominee has taken to Facebook to refute divorce rumors as well as share sweet posts for his wife Jada, such as a birthday message that included this throwback photo ‘taken at your mom’s house 20 years ago’

Smith also recently revealed he unexpected impact his latest role played in his life. In Concussion, Smith plays Dr. Bennet Omalu, a forensic neuropathologist who was the first to discover chronic traumatic encephalopathy in football players in the new movies, but admits he had some reservations about making the film because he’s a “football dad.”

“As a parent, my son played football. I loved it. I watched him,” Smith said. “I had no idea of the long term potential negative impact of repetitive head trauma.”

The pair frequently gush about each other on social media as well, with The Fresh Prince of Bel-Air alum sharing a sweet throwback photo of the couple along with a heartfelt message for Jada’s birthday.

In September he wrote: ‘I’ve told you “I love you” at least 8,285 times. And of the nearly 3.96 Billion women on the planet – there is only 1 that I want to spend the rest of my life with.’

For Will’s birthday about a week later Jada similarly gushed, writing: ‘I’m not going to pull out the calculator like you did but know this… you have a 100 percent of my heart and the rest of my days…’

Upcoming drama Concussion, in which Will plays plays Dr. Bennet Omalu, a forensic neuropathologist who was the first to discover chronic traumatic encephalopathy in football players, hist theaters Christmas Day in the US.