( CNN ) -- Neil Armstrong , the first man to walk on the moon , was honored Thursday at Washington National Cathedral in a memorial rife with mentions of heaven and earth . Hundreds of mourners , including Armstrong 's family and fellow astronauts , packed the massive house of worship for a public `` celebration of ( Armstrong 's ) life , '' three weeks after he died on August 25 at age 82 . The cathedral 's interim dean , the Rev . Dr. Francis H. Wade , called the ceremony an opportunity to `` give thanks for a life well-lived and service nobly rendered . '' Neil Armstrong , a hero who shunned fame . Armstrong earned his renown commanding the Apollo 11 space mission and landing on the moon on July 20 , 1969 , when he was 38 . `` Neil will always be remembered for taking humankind 's first small step on a world beyond our own . But it was courage , grace , and humility he displayed throughout his life that lifted him above the stars , '' NASA Administrator Charles Bolden said at the service , about an hour before he presented Armstrong 's family with the American flag that flew over Johnson Space Center on the day the space pioneer died . Bolden did n't speak just on behalf of himself and NASA . The space agency chief also relayed portions of a letter President Obama wrote to the Armstrong family , which read , in part , `` Future generations will draw inspiration from his spirit of discovery , humble composure , and pioneering leadership , in setting a bold new course for space exploration . The imprint he left on the surface of the moon , and the story of human history , is matched only by the extraordinary mark he left on the hearts of all Americans . '' Alternating between musical and prayer interludes , luminary after luminary described Armstrong as an extraordinary man who had performed extraordinary deeds , yet retained his humility and tried to diffuse the credit and fame he received among thousands of other NASA engineers , scientists , technicians and fellow astronauts . Retired Navy Capt . Eugene Cernan was the last man to walk on the moon , in December 1972 , when he commanded the Apollo 17 mission . He paid homage to the founding member of his exclusive fraternity . `` He understood the immensity of what he had done . Yet Neil was always willing to give of himself , '' Cernan said , later adding , `` No one could have accepted the responsibility of his remarkable accomplishment with more dignity and more grace than Neil Armstrong . He embodied all that is good and all that is great about America . '' Treasury Secretary John Snow , a friend of Armstrong 's , called him `` the most reluctant of heroes . '' `` With his uncommon humility and grace , Neil captured the very best of the American character and put it on display for the world to see , '' he said . Armstrong 's one small step resonated for all mankind . CNN 's John Zarrella contributed to this reoprt .
NEW : NASA gives Armstrong 's family an American flag from Johnson Space Center . Hundreds attend a memorial ceremony at Washington National Cathedral . Armstrong is remembered as an extraordinary man who shared credit with many . Armstrong , who became the first man to walk on the moon in 1969 , died on August 25 .