Rex Tillerson delivered farewell remarks to the State Department on Thursday, saying "this can be a very mean-spirited town" 10 days after President Donald Trump fired him.
"We're all just human beings trying to do our part," he said, urging in his closing for people to do an act of kindness for one another each day.
"This can be a very mean-spirited town," Tillerson said, drawing laughter and applause. "But you don't have to choose to participate in that. Each of us gets to choose the person we want to be and the way we want to be treated and the way we will treat others."
Tillerson and Trump differed on several key policies, notably the Iran nuclear deal, moving the U.S. embassy in Israel to Jerusalem, and the Paris climate accords. Their relationship was rocky throughout; at one point, Tillerson reportedly called Trump a "moron."
Tillerson offered thanks to all gathered for their contributions to the department's mission, and he also described the preparation of the transition to Mike Pompeo, the CIA Director who Trump has nominated to be the next Secretary of State.
"While the the policies and the strategies should never change, we must constantly review how the tactics are delivering on the objectives," he said.
The country faces many challenges, Tillerson said, ranging from perplexing foreign affairs to serious national security threats.
"In these times, your continued diligence and devotion to the State Department's mission has never been more necessary," he said. "As you go about your duties, each of you carrying out your individual responsibilities as well as your collective duty, it is my hope that you will be guided by and test your actions each day against the values that we have spoken about over this past year."
Tillerson called "personal integrity" the department employees' most important asset.
"Only you can relinquish it, or allow it to be compromised. Once you've done so, it is very, very hard to regain it, so guide it as the most precious thing you possess," he said.
He spoke less than five minutes and left the building to a large ovation. Tillerson will officially leave the State Department on March 31.