For a moment in his debut as a CNN commentator Thursday night, Corey Lewandowski seemed to forget that he isn't Donald Trump's campaign manager anymore. It happened when "OutFront" host Erin Burnett asked him about a Washington Post report that examined payments totaling $730,637 from the Trump campaign to a pop-up firm called Left Hand Enterprises.

"Whatever may be on Left Hand Enterprises, whatever job was supposed to be done, was done effectively and efficiently," Lewandowski said. "And if it wasn't, we'll make sure that the money is returned properly."

Lewandowski is no longer part of the "we" in the Trump campaign, and his job isn't to "make sure" that money is returned. His job now is to analyze the presidential race for CNN.

In Lewandowski's defense, he was just ousted Monday, and this was his first time on the air as a CNN employee. It will take some getting used to. But there is a very real concern — expressed by many journalists when news of Lewandowski's hiring broke on Thursday afternoon — that the former top aide to Trump won't ever leave behind the mentality of his old job.

And it's not merely a question of loyalty; it's a question of legality. Burnett addressed the issue with Lewandowski directly: "Did you sign a nondisclosure agreement when you worked for the Trump campaign?" Here's how he responded:

When I came on board the Trump campaign, like everybody else, I said what I would do is keep confidential information confidential. And I signed a document to that degree, and I don't plan on ever breaking that. My confidentiality agreement is such where information that I would be privy to and private conversations that take place between family members that are not meant for the public audience are going to be held in the closest and strictest of confidence with me.

Fine, but the real issue isn't whether Lewandowski will spill secrets. No one would expect him to do that. The issue is whether he'll be able to provide authentic analysis, criticizing his former boss as he sees fit, or whether he'll be required to put a positive spin on everything Trump says and does, as if he were still on the payroll.

Burnett read a portion of a nondisclosure agreement: "During the term of your service and at all times thereafter, you hereby promise and agree not to demean or disparage publicly the company, Mr. Trump, any Trump company, any family member, or any family member company."

"Did you sign something like that, that said no disparaging?" she asked.

Lewandowski didn't provide a yes-or-no answer:

Let me tell you who I am. And then for those who don't know me, I'm a guy who calls balls and strikes. I'm going to tell it like it is because that's how I've had my entire career, and most of the time it has been at my own detriment. People who know me know I'm a very straightforward person. I'll tell you exactly like it is, whether you like it or not. And maybe that's the reason I don't have some of the jobs I should have had or been given some of those opportunities because I'm a straightforward person.

That's not going to change. No matter what I've done or what I've said, if something is wrong, I'm going to tell people it's wrong. If something is right, I'm going to tell people it's right. So there is nothing that's going to stop me from telling the truth, in my opinion, regardless of what that is.

"Even when it's saying something bad about Donald Trump?" Burnett pressed, seeking clarification. "Right," Lewandowski replied.

So we have Lewandowski's word that he'll shoot straight and criticize Trump if he thinks the presumptive Republican presidential nominee is in the wrong. It's much too early to know whether he will live up to the promise.

In the meantime, the trouble for Lewandowski — and for CNN — is that the value of his word plummeted faster than a post-Brexit British pound after he called a reporter "delusional" for claiming in March that he had grabbed her by the arm at a news conference. "I never touched you," he insisted. Security footage later proved that Lewandowski did, in fact, grab the journalist, Michelle Fields.

This very well-covered history means his word probably won't be enough to satisfy skeptics, especially since he's being cagey about what was in the nondisclosure agreement he signed.

Until Lewandowski demonstrates that he isn't just a shill for Trump, viewers — and his new colleagues in the media — will have some doubts.