Khizr Khan is tired. His appearance Wednesday afternoon at a private meeting with a small group of Muslim and Jewish leaders in Boston was the 89th public event he has done since he electrified the Democratic National Convention last summer.

But when the Anti-Defamation League invited him to Boston to speak to more than 1,400 teenagers at its annual Youth Congress this week, the Pakistani-American lawyer and Gold Star father did not hesitate to continue his national tour speaking out on behalf of religious liberty and minority rights.

“I would have walked to this opportunity to stand in front of these future leaders and leave them with a thought or two about what an important role lies ahead of them,’’ he said in an interview. “How this nation, even now, looks up to them to find solutions, to lead us in a different direction. How they should take care of each other.’’

Khan is worried, certainly, about the direction the country has taken under President Trump. He is deeply concerned about the policies and about the hatred that he says was always lurking in some quarters but now lies exposed.

“But I’m hopeful for rule of law,’’ he said. “The rule of law is the solution to what is taking place in my country. It is the rule of law that has frozen the executive orders in their track. And it will continue to deal with the future violations of civil liberties and civil rights.’’

Everywhere he goes, he added, he finds displays of unity and interfaith solidarity to buttress his abiding faith in America. He found it Wednesday in Boston, he said, talking with some of the area’s Muslim and Jewish leaders.

“I have seen the optimism in the words and eyes of those who come to such gatherings, they’re concerned, they’re worried, but there is optimism,’’ he said. “And that optimism sometimes comes from just reminding ourselves — look where we were 20 years ago, 30 years ago, 40 years ago.’’

Until last summer, Khan, now one of the most recognizable Muslims in America, and his wife, Ghazala, lived a relatively quiet life in Charlottesville, Va., where they moved after the death of their middle son. US Army Captain Humayun Khan was just 27 when he was killed in 2004 by a car bomb in Iraq. He saved the life of his fellow officers in the tragedy and was posthumously awarded the Purple Heart and Bronze Star.

When the Khans were invited to address the convention, their friends and other two sons advised against it, Khan said, arguing the loss of privacy and dignity wasn’t worth it.

The couple sat for two days in part of a room in their house dedicated to their son, surrounded by his uniform and his medals, thinking it over. They were safe. Their children were safe.

But the children of many of their friends — Muslim, Indian, Hispanic — were not doing so well, Khan said. They were nervous, not doing their homework, not eating properly. For reassurance, some of them brought their kids to Khan, who carries the Constitution in his pocket and likes to hand out copies to visitors to his home.

Khan said he and his wife kept asking themselves what their son would do, and finally concluded their son — who always stood up to bullies — would have wanted them to accept the invitation.

“It was on behalf of those worried hearts . . . and those children,’’ he said.

His denunciation of Trump for denigrating Muslims and his rebuke of the then-Republican presidential nominee for targeting immigrants and other minorities were among the most memorable moments of the convention. Khan suggested Trump had never read the Constitution.

“I will gladly lend you my copy,’’ he said from the stage in Philadelphia, waving his pocket-sized version. “In this document, look for the words ‘liberty’ and ‘equal protection of law.’ ’’

Trump’s response — to criticize Khan for attacking him and suggesting that Ghazala “wasn’t allowed to’’ speak — only drew more attention to the Khans. Khizr Khan went on to campaign on behalf of Hillary Clinton, the Democratic nominee.

Khan says he doesn’t believe Trump dislikes Muslims — “he is so self-absorbed, he is incapable of thinking anything more than Trump’’ — but he said Trump’s advisers are giving him talking points that draw heavily on the themes that Adolf Hitler favored: fear of the stranger, economic insecurity.

But, Khan said, “this is not 1930, 1940, this is 2017, and the world and . . . humanity have moved forward. You see the resistance in the country.

He does not accept honorariums for his speeches, he said, but instead asks his hosts to donate to a scholarship fund at the University of Virginia, where his son attended college.

Robert Trestan, director of the Anti-Defamation League’s New England office, said Thursday’s Youth Congress is not partisan; the annual gathering is an opportunity for students to learn more about civil liberties, he said. This year’s theme, Trestan said, is “the different perspectives people bring to living in the US.’’

It’s not the first time Khan has been in Boston since the campaign ended. Last month, Khan spoke at Harvard University, where he earned his master’s degree in law in 1986, renting the cheapest studio apartment he could find, on High Street in Medford, he recalled with a laugh.

“I was asked by Dean [Michael D.] Smith at the end of the class what did I learn at Harvard, and my response was that I learned how little I know,’’ he said. “I learned that whatever I know, I should speak from here.’’

He tapped his heart.

Lisa Wangsness can be reached at lisa.wangsness@globe.com.