As President Barack Obama prepares to hand over the reigns of the White House to President-Elect Donald Trump, T.I. took a moment to honor the legacy and contributions of America’s first African-American commander in chief. In the first of a series of open letters, Tip shares his thoughts on what President Obama has meant to him and the entire country.

The Atlanta rapper and actor sat with the New York Times and explained the impetus behind the letters is “using my platform to be a voice for those who can’t speak for themselves.” This comes after a pair of politically-charged releases from T.I. in 2016 with the Us Or Else EP and the full album, Us Or Else: Letter To The System.

With a renewed sense of purpose to use his platform for social change, T.I. continued that track in the open letter:

“You entered humbly into our worlds from the streets of the South Side of Chicago and galvanized a generation. You resonated from the barbershops to the airwaves to the streets of every hood across America. Many of US did not know your name, nor did we truly understand the impact you would have on the world in the years, months and days that followed.

“As I reflect, I am filled with gratitude, outrage, grief, anger, humility and appreciation, both for the things you helped bring to light and the many things we still have yet to realize.

“For years you fought to keep this nation from the very thing we have now become.”

The Obama family held its final party last night at the White House, which was attended by the likes of Wale, Usher, and several other stars.

The entire letter and T.I.’s conversation with the Times can be viewed here.