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LYNCHBURG, Va. - Delivering the commencement address at the evangelical Liberty University this morning, Mitt Romney evoked stories of his faith, albeit broadly and without mentioning his own Mormon faith specifically, telling students that their relationship with God will "make for a good life" and reasserting his opposition to same-sex marriage.

"The best advice I know is to give those worldly things your best but never your all, reserving the ultimate hope for the only one who can grant it," said Romney, addressing the more than 6,000 students who participated in the ceremony, held on the football field known as the "Home of the Flames."

"All that you have heard here at Liberty University - about trusting in God and in His purpose for each of us-makes for more than a good sermon. It makes for a good life," he said.

Romney, who follows in the footsteps of many politicians and public figures who have come to the University to appeal to the conservative core of his party, gave what was one of the most religious speeches of his campaign thus far.

"People of different faiths, like yours and mine, sometimes wonder where we can meet in common purpose, when there are so many differences in creed and theology," said Romney. "Surely the answer is that we can meet in service, in shared moral convictions about our nation stemming from a common worldview."

"That said, your values will not always be the object of public admiration," said Romney, whose own faith has been scrutinized throughout his career. "In fact, the more you live by your beliefs, the more you will endure the censure of the world.

After a week that has been all consumed by the debate over same-sex marriage, President Obama announcing he supports it and Romney saying he does not, Romney took his time at the microphone here to tell the crowd of more than 30,000 that "Marriage is a relationship between one man and one woman."

"As fundamental as these principles are, they may become topics of democratic debate from time to time," said Romney, to a mounting applause. "So it is today with the enduring institution of marriage."

Evoking the name of his one-time GOP rival Sen. Rick Santorum, who endorsed his candidacy last week, Romney said it was Santorum who told him about a study that showed the probably of being poor is significant lower "for those who graduate from high school, get a full-time job, and marry before they have their first child."

"Culture, what you believe, what you value, how you live, matters," said Romney.

The address was not without a few more light-hearted moments, Romney at one point joking that he hopes he "hasn't seen the last" promotion of his career.