Monday, Jan. 15 is the time people across the U.S. remember and honor slain civil rights leader Rev. Martin Luther King Jr.

King, the country’s most visible advocate for voting and civil rights, was killed by an assassin on April 4, 1968. MLK Day is a federal holiday, though it was not made official until 18 years after his assassination.

King’s legacy of nonviolent protest lives on today as do some of his most inspirational quotes. Here are 15 most meaningful and inspirational quotes from King:

“It is not possible to be in favor of justice for some people and not be in favor of justice for all people.”

“We’ve got some difficult days ahead. But it really doesn’t matter with me now because I’ve been to the mountaintop… I’ve looked over and I’ve seen the promised land. I may not get there with you. But I want you to know tonight that we as a people will get to the promised land.”

“Change does not roll in on the wheels of inevitability, but comes through continuous struggle.”

“Darkness cannot drive out darkness; only light can do that. Hate cannot drive out hate; only love can do that.”

“Faith is taking the first step even when you don’t see the whole staircase.”

“I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin, but by the content of their character.”

“There comes a time when one must take a position that is neither safe, nor politic, nor popular, but he must take it because his conscience tells him it is right.”

“We must develop and maintain the capacity to forgive. He who is devoid of the power to forgive is devoid of the power to love. There is some good in the worst of us and some evil in the best of us. When we discover this, we are less prone to hate our enemies.”

“Injustice anywhere is a threat to justice everywhere.”

“If you can’t fly then run, if you can’t run then walk, if you can’t walk then crawl, but whatever you do you have to keep moving forward.”

“Let no man pull you low enough to hate him.”

“In the end, we will remember not the words of our enemies, but the silence of our friends.”

“If I cannot do great things, I can do small things in a great way.”

“That old law about ‘an eye for an eye’ leaves everybody blind. The time is always right to do the right thing.”

“A genuine leader is not a searcher for consensus but a molder of consensus.” – Martin Luther King, Jr.