On his last day as Secretary of Defense, Robert Gates received surprise honors during a farewell ceremony at the Pentagon. "Bob, this is not in the program but I would ask you to please stand," said President Obama. "The highest honor I can bestow on a civilian is the Presidential Medal of Freedom. It speaks to the values we cherish as a people and the ideals we strive for as a nation," he continued, presenting Gates with the prestigious award.

"It is a big surprise. But we should have known a couple of months ago you'd get pretty good at this covert ops stuff," joked Gates following the President's presentation.

After a series of farewell events, including a dinner hosted by President Obama and the First Lady at the White House Thursday evening, Secretary Gates will end his four decade-long civil service career. "Becky, we're really going home this time," he said turning toward his wife during Thursday’s outdoor ceremony. Former CIA Director, Leon Panetta will assume the duties of Secretary of Defense following Gates' retirement.

On Wednesday, the Pentagon distributed a farewell message from Gates to "all U.S. military personnel, active and reserve, around the world."

"For four and a half years, I have signed the orders deploying you, all too often into harm's way. This has weighed on me every day. I have known about and felt your hardship, your difficulties, your sacrifice more than you can possibly imagine," the statement read.

Known for his emotional and often candid comments when speaking to the troops, Gates thanked America's service members one last time during Thursday's ceremony, "Looking forward to this moment, I knew it would be very difficult for me to adequately express my feelings for these young men and women at least in a way that would allow me to get through this speech," he said. "I'll just say here that I will think of these young warriors, the ones who fought, the ones who keep on fighting, the ones who never made it back until the end of my days," he continued.

Gates, who has served under eight presidents during his career, provided one suggestion for incoming Secretary Panetta: "My parting advice for Leon is to get his office just the way he likes it, he may be here longer than he thinks."