A Republican congressman slammed GOP colleague Lauren Boebert’s recent call to end separation of church and state in the US, warning: “There is no difference between this and the Taliban.”

“We must opposed [sic] the Christian Taliban,” Adam Kinzinger, a US representative for Illinois, said on Wednesday. “I say this as a Christian.”

Kinzinger, who is on the committee investigating the deadly January 6 attack on the US Capitol, was referring to comments that the Colorado Republican congresswoman made at a church in her state. During an address at the Cornerstone Christian Center in Basalt, Boebert said she was exhausted by the separation of church and state principle; this principle is a key tenet of the US constitution.

“The church is supposed to direct the government,” Boebert said, according to the Hill. “The government is not supposed to direct the church. That is not how our founding fathers intended it.”

“I’m tired of this separation of church and state junk – that’s not in the constitution. It was in a stinking letter and it means nothing like they say it does,” Boebert also remarked, reportedly prompting applause. The extreme rightwing politician routinely makes comments that foment the culture war: she opposes gun control, questions the efficacy of vaccines, and the 2020 election outcome.

Boebert was alluding to an 1802 letter that Thomas Jefferson – who was president at the time – sent to a church organization. In this correspondence, Jefferson said that the American public had constructed “a wall of separation between Church and State”, the Hill said.

Despite Boebert’s remarks about the letter, the first 10 US constitutional amendments – called the Bill of Rights, as they sought to confirm the “fundamental rights” of US citizens – were ratified on 15 December 1791. That means they predate the letter.

The first amendment, which is part of the Bill of Rights, states: “Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances.”

This reference to religion is the “Establishment Clause”. The Cornell Law School’s Legal Information Institute explained that this clause “prohibits the government from making any law ‘respecting an establishment of religion’”.

“This clause not only forbids the government from establishing an official religion, but also prohibits government actions that unduly favor one religion over another,” the Institute continued. “It also prohibits the government from unduly preferring religion over non-religion, or non-religion over religion.”

The US supreme court, which now has a super majority of conservative justices, has increasingly indicated openness to permitting religion in the public sphere. Earlier in June, the panel rejected a Maine statute that had barred religious schools from receiving tuition assistance from public money, the Hill noted.

The justices also ruled in support of a one-time public high school football coach who was suspended for praying with players at the 50-yard line following games. In her dissent on the ruling, the liberal justice Sonia Sotomayor said: “This court continues to dismantle the wall of separation between church and state that the framers fought to build.”