President Barack Obama made a clear declaration of his Christian faith on Thursday and seemed to express some frustration that his beliefs continue to be called into question.

“Let me tell you, these past two years, they have deepened my faith,” Obama told a ballroom full of applauding believers at the annual National Prayer Breakfast in Washington.

“The presidency has a funny way of making a person feel the need to pray.”

He detailed how, after a non-religious upbringing, he came to define himself as a Christian.

“A call rooted in faith is what led me, just a few years out of college, to sign up as a community organizer for a group of churches on the south side of Chicago,” he said.

“And it was through that experience, working with pastors and laypeople, trying to heal the wounds of hurting neighborhoods, that I came to know Jesus Christ for myself and embrace him as my Lord and Savior.”

Obama joked that he prayed for patience while watching his children grow up.

“Lord, give me patience as I watch Malia go to her first dance, where there will be boys,” he said, referring to his oldest daughter, to laughter from the audience.

“Lord, have that skirt get longer as she travels to that dance.”

He said his faith sustained him when he could not do more to help Americans dealing with the rough economy.

But he also seemed to vent frustration that despite more than 20 years as a practicing Christian, people still question his religious persuasion.

Polls show many Americans believe Obama is a Muslim.

“My Christian faith then has been a sustaining force for me over these last few years, all the more so when Michelle and I hear our faith questioned from time to time,” he said.

“We are reminded that ultimately what matters is not what other people say about us, but whether we’re being true to our conscience and true to our God.”

Photo credit: Reuters/Kevin Lamarque (Obama speaks at National Prayer Breakfast)