President Bush on Monday hailed the Rev. Martin Luther King Jr. as a towering figure and called on the nation's people to honor the slain civil rights leader by helping those in need.

"Our fellow citizens have got to understand that by loving a neighbor like you'd like to be loved yourself, by reaching out to someone who hurts, by just simply living a life of kindness and compassion, you can make America a better place and fulfill the dream of Martin Luther King," Bush said at a library named for the slain civil rights leader.

With first lady Laura Bush at his side, Bush spoke briefly on the federal holiday honoring the birthday of King, who would have been 79 on Jan. 15.

An advocate of peaceful resistance and equality for people of all races, King was assassinated in April 1968.

Bush said that King's holiday offers a chance to "renew our deep desire for America to be a land of promise for everybody, a land of justice, and a land of opportunity." He said it should be a "day on" of volunteering -- not a day off -- and encouraged people to do community service year-round.

The setting for Bush was the Martin Luther King Jr. Memorial Library in downtown Washington. The building features a colorful mural that depicts scenes from King's life and celebrates his role in the march toward social justice.

"Martin Luther King is a towering figure in the history of our country," Bush said. "And it is fitting that we honor his service and his courage and his vision."

Bush spoke after participating in a story-time session with a handful of children who grew shy in his presence. The president posted a few pictures on a bulletin board as the young students learned how King fought to change unfair laws.

When the kids were asked how they could make the world a better place, none of them spoke up. So Bush did for them.

"Love your neighbor," he said emphatically. "Volunteer," chimed in the first lady.

Bush has marked the King holiday in different ways during his presidency. Among other events, he has viewed the Emancipation Proclamation at a special showing at the National Archives, placed a wreath at King's grave, spoken at a predominantly black Baptist church and helped spruce up a high school.