The TV adventurer also said while he may not go to church as much as he would like, he asks God to help him everyday.
He told the Radio Times: "I try to start every day by kneeling down and saying, 'Lord Jesus, I ain't got it all right, and I'm nervous about today.
"I will give it my all, but will you help me? It's never more complicated than that. I probably don't go to church enough, but my faith is a quiet, strong backbone in my life, and the glue to our family."
Bear Grylls also said he has "no problem at all with gay marriage."
Clarifying his position, he said: "I really struggle with religion just because it's the source of so much conflict and disunity.
"The heart of Christianity is just about saying, 'I need help, and will you be beside me?' And I don't think anyone has a problem with that."
"What they don't want is religion - and I totally get that."
Mr Grylls was recently pictured praying with the US President Barack Obama, also a Christian, in Alaska.
The US President joined the explorer for a special episode of his programme Running Wild With Bear Grylls.
The pair trekked Alaska witnessing the effects of climate change firsthand, where warming waters and rising sea levels are posing a threat to locals, landscapes and wildwife.
He has also previously said how doing an Alpha Course helped him and his wife in their walk with God: "Shara and I did it together."
"It helped us in a very low-key, unpressured way to explore some big questions.
"As a family it has given us a really lovely quiet faith that has been a powerful thing in our lives."