President Barack Obama urged Americans to engage in the "debates of our time," such as equality - including debates on homosexuality - climate change, war, and global security, in his second inaugural address Monday.

Speaking before a crowd gathered at the National Mall in Washington D.C., Obama outlined his views on God, United States history, his philosophical approach to governing and values he holds dear as he set his agenda for his next four years in office.

The President, speaking in front of hundreds of thousands in front of the nation's capitol urged Americans to embrace their duty as citizens.

"You and I, as citizens, have the obligation to shape the debates of our time- not only with the votes we cast, but with the voices we lift in defense of our most ancient values and enduring ideals," he said.

The president's speech addressed some of those issues, including his commitment to support the nation's health and pension systems, address climate change, the war in Afghanistan, global security, and equality for all citizens with a focus on the nation's civil rights history and debates surrounding homosexuality.

He urged Americans to work "knowing that our work will be imperfect."

"We must act, knowing that today's victories will only be partial and that it will be up to those who stand here in four years and 40 years and 400 years hence to advance the timeless spirit conferred to us in a spare Philadelphia hall," he said.

He cited the nation's founders, who declared their independence from England in 1776 in a pre-constitutional document known as the Declaration of Independence.

Obama quoted the document which stated: "We hold these truths to be self-evident, that all men are created equal; that they are endowed by their Creator with certain unalienable rights; that among these are life, liberty, and the pursuit of happiness."

He said the nation was on a "never-ending journey to bridge the meaning of those words with the realities of our time."

"For history tells us that while these truths may be self-evident, they've never been self-executing; that while freedom is a gift from God, it must be secured by His people here on Earth," he said.

He also said America's prosperity "must rest upon the broad shoulders of a rising middle class," while outlining goals for overnment inclding increased use of technology, tax code reform, increasing job skills and education. He defended the nation's medical and pension programs saying they "do not sap our initiative, they strenthen us."

"They do not make us a nation of takers; they free us to take the risks that make this country great," he said.

Obama also addressed climate change, saying a failure to do so "would betray our children and future generations." He said "none can avoid the devastating impact of raging fires and crippling drought and more powerful storms."

He said the nation should lead in a path to developing sustainable energy sources, use technology to generate new jobs and industries.

"That's how we will maintain our economic vitality and our national treasure -- our forests and waterways, our crop lands and snow-capped peaks. That is how we will preserve our planet, commanded to our care by God," he said.

In reference to the war in Afghanistan, he said "we, the people still believe that enduring security and lasting peace do not require perpetual war." The U.S. is set to end combat activity in the middle-eastern nation in 2014.

He also said the U.S. would "remain the anchor of strong alliancees in every corner of the globe," and renew its ability to "manage crisis" abroad, by supporting democracy in places from Asia to Africa, from the Americas to the Middle East."

"And we must be a source of hope to the poor, the sick, the marginalized, the victims of prejudice –- not out of mere charity, but because peace in our time requires the constant advance of those principles that our common creed describes: tolerance and opportunity, human dignity and justice," he said.

He also reserved a portion of the speech to expound on equality in terms of race, sex, sexuality, voting rights, immigration and safety.

He made references to historic references to the women's suffrage movement in the 1840s, voting rights marches for blacks in the 1960s, and gay rights riots also in the 1960s.

It is now our generation's task to carry on what those pioneers began. For our journey is not complete until our wives, our mothers and daughters can earn a living equal to their efforts," he said. "Our journey is not complete until our gay brothers and sisters are treated like anyone else under the law."

He began the day by attending a service at St. John's Episcopal Church, where he was called on by Pastor Andy Stanley of North Point Community Church in Alpharetta, Ga. to use his power for others.

"You leverage that power for the benefit of other people in the room," he said, according to the Associated Press.

"Jesus would say to do less than that would be to declare yourself greater than me.""Mr. President, you have an awfully big room. My prayer to you is to leverage that power for the stewardship of our nation."