For the International Church of Cannabis in Denver, there were three reasons to celebrate on Thursday.
First, it was opening day. The church, a more than century-old building recently adorned with brightly colored paintings by the artists Kenny Scharf and Okuda San Miguel, welcomed the public early in the afternoon, at which time no cannabis consumption was allowed inside.
“It seemed to be a nice steady flow of people,” said Lee Molloy, a founder of the church and a member, who estimated that a couple of hundred people had come by.
Second, it was April 20, an unofficial holiday of sorts for marijuana users. There have been disagreements as to why the number 420 has taken on significance in the cannabis community, but Steve Berke, the church’s media relations director, did not want to worry about that.
“It’s a number that everybody’s adopted, and we’re adopting it too,” he said. The church closed its doors to the public after 2 p.m. local time, leaving only invited visitors, who were allowed to light up for a private 4:20 ceremony.
And third: A challenge to the church’s legality, in the form of an amendment proposed in the state’s House of Representatives, was shut down almost as quickly as it arose on Thursday morning.
All told, it was a good day for the church’s membership, which ballooned to more than 200 people from around 50 this week after increased media attention.
Colorado legalized recreational marijuana in 2012 and has been fine-tuning its regulations ever since. It is still illegal to smoke in Denver’s public spaces. And some decisions on legal usage are still left up to cities, creating a patchwork of laws that legislators are still working to consolidate.
Mr. Berke and Mr. Molloy are founding members of Elevation Ministries, the religious nonprofit behind the church. “We thought we could do something different, something unique,” Mr. Berke said, explaining that the church adheres to no specific dogma.
“We’re building a community of volunteers, and the common thread is that they use cannabis to positively influence their lives, and they use cannabis for spiritual purposes,” he said.
Not everyone was happy to hear about the new church. Dan Pabon, a Democrat in the state’s House of Representatives, had a bill on marijuana regulation making its way through the legislature. On Thursday morning, he tried to add an amendment banning cannabis consumption in churches.
It was, he said, a move inspired by the International Church of Cannabis.
Elevation Ministries “is basically leveraging and capitalizing on the usage laws that we have in Colorado,” he said. “I think it offends both religious beliefs everywhere, as well as the voters’ intent on allowing legalization of marijuana in Colorado.”
But some of Mr. Pabon’s fellow representatives did not buy it.
“I thought that this was engaging in a nanny state,” said Joe Salazar, a Democrat. “I completely disagree with saying that a person can worship in one particular way or the other, and that that’s going to be regulated by the state.”
In the end, the amendment was not formally introduced. Still, Mr. Pabon hopes the Senate will consider bringing it up again in the coming weeks.
Mr. Berke saw Mr. Pabon’s amendment as a clear example of religious persecution. “And for those who accuse us of creating a church as an excuse to smoke weed, we’re in Denver,” Mr. Berke said. “We can smoke anywhere. I think he should be embarrassed.”
Mr. Salazar acknowledged the unpredictable nature of cannabis legislation. “This is fly-by-the-seat-of-your-pants, blazing-the-trail kind of policy-making,” he said. “And Colorado is a leader on it.”
Mr. Molloy said that while church members have done — and will do — their due diligence abiding by existing laws and meeting with city officials, it would be a constant challenge to stay abreast of changing regulations. “We’re jumping through all the hoops the state and city require us to jump through,” he said.
But he added that he was proud to see the church open its doors. “It’s a world-class piece of art,” he said of the renovated building. “It’s a masterpiece. And I think the city of Denver is lucky to have it.”