Here's the farewell letter James Comey sent his former FBI colleagues after Trump fired him
The letter, obtained by CNN's Shimon Prokupecz, also urges FBI staff members to continue the agency's mission of "protecting the American people and upholding the Constitution."
"I'm not going to spend time on the decision or the way it was executed," Comey said in the letter. "I hope you won't either. It is done, and I will be fine, although I will miss you and the mission deeply."
He continued: "My hope is that you will continue to live our values and the mission of protecting the American people and upholding the Constitution. If you do that, you too will be sad when you leave, and the American people will be safer."
On Thursday, Comey is testifying before the Senate Intelligence Committee, speaking publicly for the first time since Trump unexpectedly fired him on May 9. In his prepared opening remarks, which the committee released Wednesday, Comey wrote that Trump asked for his loyalty during a dinner in January, and requested that he drop the FBI's investigation into former national security adviser Michael Flynn in an Oval Office meeting in February.
The firing immediately raised suspicions that the president was trying to stifle the FBI's ongoing investigation into whether the Trump campaign colluded with Russia to meddle in the 2016 election. Subsequent reports said that Comey had asked the White House last week for more resources for the investigation and that the investigation was "accelerating."
Senators on both sides of the aisle are poised to dig into the firing on Thursday, and ask about the president's efforts to influence the Russia investigation. It is set to be a historic showdown.