Promoters have emphasized that masks will be mandatory and social distancing enforced, and they have questioned whether it is discriminatory for the government to have set more lenient restrictions on church gatherings than on concert venues.

“The directive is discriminatory because the virus does not know if it’s in a body in church or high school or a music venue,” said Mike Brown, a representative for Temple Live, in an interview. “Not that I have anything against church, but if you can go to a church and it’s a public assembly, there is no difference. How is it OK for one group to have a public meeting and it’s not OK for a music venue to have the same opportunity?”

The governor, however, is not backing down.

In an emailed statement from his office Thursday, Governor Hutchinson said: “As advertised, this concert does not comply with our Department of Health directives for indoor entertainment venues,” he said. “I appreciate the venue owners’ working to enforce social distancing and the wearing of masks to protect the concertgoers, but the concert remains outside of the state’s pandemic directive.”

Mr. Brown said the event was conceived before the governor’s recent announcement, in anticipation that the rules would be relaxed, that he had been blindsided by the lingering limitations, but that he was still working to negotiate with state officials.

The mayor of Fort Smith, George B. McGill, said the city would support the state’s policy for reopening concerts because the governor’s approach had so far worked well and because he didn’t want to set back the progress the city had made in combating the coronavirus. The county has had less than two dozen cases and no deaths from the virus.

“My hope is that everybody cools off and let’s be ’60s cool for a minute and work together,” the mayor said in an interview — and at the end there will be “a win-win for all involved.”

He did not say what that “win-win” might be, though he wondered whether Mr. McCready might be prepared to return at a slightly later date.

Some legal experts said Temple Live could face a struggle in the courts if it tried to test its discrimination claim legally, especially if all concert venues were being treated the same way. Whitfield Hyman, a civil rights and criminal defense attorney in Fort Smith, said a commercial business like a music venue is typically given less constitutional protection than a religious gathering in terms of speech.

“I imagine that the courts will find similarly in a case about the right to assemble,” Mr. Hyman said. “A person probably has more legal rights to have an assembly at a home or a church than a business.”

Asked what action it could take if the show were to proceed, the governor’s office said it did not want to speculate. “The Department of Health directive,” it said in a statement, “does have authority to legally restrict gatherings that are not in compliance, but the governor remains confident that the issue will be resolved before such action becomes necessary.”

Arkansas is not the only state to reopen. Missouri has already allowed concertgoers to attend live events from May 4, though people have to stay six feet apart. No major promoters have presented a show there yet, though.

“We are unaware of any promoters hosting large gatherings or events in Missouri prior to June 30,” Shani Tate, at the Sprint Center, an arena in Kansas City, said in an email.

Missouri’s efforts to reopen for shows drew criticism from The Kansas City Star, which called it “a woefully premature green light for socially distanced concerts,” in an editorial. The article was titled, “Why does Missouri want to be the first to allow concerts, live events during Covid-19?”

Many local officials in Missouri are continuing to forbid concerts for now. “We will continue to be guided by data, not dates,” the St. Louis Mayor, Lyda Krewson, said in a tweet.

In Fort Smith, the social distancing measures Temple Live has introduced mean the concert, if it goes ahead, could provide a glimpse of what live events might look like in the age of the coronavirus. Fans will have their temperatures taken when they arrive. They will be directed along one-way walkways, and limited to 10 people in the bathroom at any one time. They will sit in “pods,” or small gatherings, restricted to friends and relatives who are comfortable sitting together. Each group, between two and 12 in number, will have to be six feet from any other.

Mark Mulligan, a music industry analyst, said it was still too early to say whether the early reopening of some shows like the one in Fort Smith heralded a restart of the stalled concert industry.

He said consumer confidence was likely to remain fragile and could easily be set back if the virus returned in future waves.

“People are going to remain cautious about going into venues, and small venues are even more at risk,” he said.

Mr. Brown said the McCready concert was on track to being sold out, and, depending on how this week’s concert goes, if it goes at all, he would like to schedule more soon. “It’s going to be strange for the artist and for the fans,” he said. “But it’s better than what we have today.”

Mr. McCready will be taking the stage with three bandmates (trying to keep a safe distance apart but not wearing masks) and said the measures the venue was taking were “the best situation you could ask for.” Fans were desperate for new music, he said, and they could decide for themselves whether they should attend.

“Each to his own,” Mr. McCready said in an interview. “I am just excited to be playing.”