If you are ever in any serious trouble, you could do a lot worse than have James Comey testify on your behalf. And if you ever study to be an actor, you could do a lot worse than take notes from Mr. Comey’s testimony before Congress.

The former F.B.I. director, who spoke yesterday before the Senate Intelligence Committee on the events leading up to his firing by President Trump, was so earnest he did not sound like someone who was trying to be earnest. In his navy suit and plum colored tie, his quick, clipped answers to the questions posed by the panel, “Yes,” “No,” “That’s correct,” were so matter of fact that they did not sound like someone trying to be matter of fact.

If you ever study to be an actor, you could do a lot worse than take notes from Mr. Comey’s testimony before Congress.

As he talked about his one-on-one dinner with Mr. Trump, his hopes that there were tapes of their conversation, his leaking of a memo, Mr. Comey kept himself still and grounded—but not like someone who was trying to appear still and grounded. The former director rarely looked down or glanced around the room, a signifier of shiftiness, but not in the manner of one who was trying to keep a forward gaze and seem unshifty.

In other words, he didn’t seem like he was acting—the greatest compliment you can give an actor. Because if you are testifying before Congress on matters that could bring down a president, regardless of how true your testimony is, you are going to start playing some version of yourself. You are going to perform. It’s not that Mr. Comey told a bunch of lies and covered them up with a prize-winning performance. It’s that facts can sound like lies when you tell them under pressure. Mr. Comey, who has had experience testifying before Congress, didn’t buckle to the pressure.

James Comey didn’t seem like he was acting—the greatest compliment you can give an actor.

Actors often talk about “dropping in” to a character. Tom Hanks was really “dropped in” to Captain Miller in “Saving Private Ryan.” He knew his lines so completely, he owned the words and actions so thoroughly, there was little space between him and the World War II soldier. You believed him.

Or Judi Dench in “Shakespeare in Love.” Ms. Dench’s stillness was her most powerful asset. Stillness is an actor’s great weapon that allows us to focus on the words, on the character. Ms. Dench completely owned every moment she was on screen. When you let yourself be utterly still, people can see you. Really see you. You are not bringing your performance to them. With radical stillness you are drawing them into yourself.

A director once told a company of actors that the most important thing an audience is asking during a play is, “What happens next?” But if an actor is self-indulgent in his “moments,” he in essence stops the play and makes the audience focus on him. If an actress puts too much into her character, makes it showy and fantastic beyond what the character demands, you may admire the actress but miss the story. Is “Twelfth Night” about Viola or about the actress playing Viola? The actress should be the channel through which the story is told, not the story herself.

And so with James Comey. As he implied that the president tried to quash the investigation into former national security adviser Michael Flynn, he was mostly still, centered. He got his words out and made it about the testimony, not about him. For the most part he underplayed, which works for television. The version of himself he “portrayed” on camera was probably the actual version of himself.

Even his more impassioned, speechy moments, “I hope we love America equally” and “we remain that shining city on a hill,” were kind of sweet and earnest. An F.B.I. director! A man who can train 10,000 guns on your everyday scruffy and peaceable anti-capitalist was sort of adorable! He earned his dramatic moments with a testimony of grounded truth-telling. The Secretive Lawman, the Lord of Infiltration, the Emperor of Subterfuge, (the Destroyer of a presidential campaign?) was so real and likeable.

In a deeply skeptical age, I suppose we still want someone to believe in. (Maybe because it is such a skeptical age.) Perhaps, like a lot of actors, Mr. Comey has been playing a role (the Upright G-man) for so long that he doesn’t truly know who he is. Either way, I commend his testimony to the performers out there. For a few hours, James Comey gave us something to believe in—even if we believe only because we are desperate for integrity, whether it’s an act or not.

Joe Hoover, S.J., is America’s poetry editor and producer of a new film, “The Allegory.”