I was one of a small group of Catholics in attendance at the “Conversation About America’s Future” on June 21, 2016, which featured Donald Trump and Dr. Ben Carson. Most of the 1,000 people in attendance were evangelical and charismatic Protestants. I was honored to have been invited and I am very glad I attended.

Trump addressed with conviction and clarity the threats to the free exercise and free speech rights of the Christian church. He pledged to defend those rights if elected President of the United States — and getting specific, he called for the repeal of the Johnson Amendment. Let me explain why repealing that bad law is so important.

On July 2, 1954, an ambitious U.S. Senator named Lyndon Johnson offered an amendment to an overhaul intended to “modernize” the Tax Code of the United States. It passed. The Johnson Amendment “absolutely prohibits” 501(c)(3) tax-exempt groups from “directly or indirectly participating in, or intervening in, any political campaign on behalf of (or in opposition to) any candidate for elective public office” or making “contributions to political campaign funds or public statements of position.”

The Johnson Amendment makes exceptions for “certain voter education activities (including presenting public forums and publishing voter education guides) conducted in a non-partisan manner … voter registration and get-out-the-vote drives,” provided they do not favor or oppose some candidate or group of candidates.

Sounds reasonable, right? In fact, the Johnson amendment has proven to be a dangerous tool, allowing political appointees at the Internal Revenue Service (IRS) to determine when moral issues become political issues — and effectively censor churches and religious organizations with the threat of crippling penalties and loss of tax exempt status.

The IRS is the sole interpreter of ambiguous phrases in the law’s provisions. For example, the law “allows” voter registration and education drives. But what constitutes “evidence of bias” and “favoring a candidate”? Who decides? Whomever the current president has appointed head of the IRS will make the final call. How much scrutiny do you think that urban churches like that of Rev. Jeremiah Wright (Obama’s old pastor) came under over the past eight years? Remember how Obama’s IRS aggressively targeted Tea Party groups for audits. Was the IRS fair to morally conservative churches? I can tell you from first-hand experience: it was not.

In practice, the Johnson Amendment discards the Constitutional presumption of innocence. If the IRS accuses a church or religious organization of crossing the line, it can lose its exemption immediately and be subject to punitive fines, while it tries to prove its innocence — bearing the burden of proof, instead of its accusers bearing it. This exerts a chilling effect on churches who are not aligned with the political priorities of whoever is currently President.

The First Amendment to the Bill of Rights begins, “Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof.” The Johnson Amendment makes a mockery of that language, coming closer to the mere hour-a-week-on-Sunday “freedom of worship” that President Obama has often spoken of rather than the actual words of our Constitution.

“Free exercise” includes engaging in commerce, participating in politics and pursuing liberty and happiness as a full participant in the American polity. The Free Exercise right was meant to protect citizens’ deeply held moral and religious beliefs, even outside the walls of their places of worship. It was also meant to give the church a robust freedom to influence and serve the common good. It was never meant to empower the government to censor the church or restrict its participation. If it had, the churches could not have led the fight against slavery in the 1840s, eugenics in the 1920s or segregation in the 1950s and ’60s. Had the Johnson Amendment been in place during those decades, and read to their advantage by political appointees, we would live in a much bleaker, less human country today.

We have accepted the secular supremacist spin used to interpret our founding documents by progressives like Harvard Professor Mark Tushnet, who sees orthodox Christians as the moral equivalent of the defeated Nazis and Japanese — discredited losers who must be crushed without mercy or respite. It is people with views like Tushnet’s who end up on our nation’s highest courts. And we let them beat us down. We numbly accept the notion that a bloated agency of the federal government, drunk with free-flowing power, is the arbiter of interpreting my religious freedoms and yours. That was not what our nation’s founders intended.

There was no Internal Revenue Service when the Constitution and Bill of Rights were drafted. Christian leaders, pastors, ministers, priests and public servants were welcomed and honored for the most part. Their message and participation were both seen as serving the common good.

Using the Johnson Amendment, the IRS often seeks to censor Christian claims that the right to life, as well as natural marriage between one man and one woman, are both written in the “laws of nature and of nature’s God,” and so should be recognized in the civil law. They exclude such positions as “religious.” They rule them out as unfit for public display and try to silence their advocates when they can.

The government’s agents increasingly come into our churches, organizations and institutions, claiming that our obligation as faithful Christians to address the major moral issues of our age from our pulpits amounts to “political” activity. Then they threaten to revoke our tax exempt status. Will they soon insist that we may not preach or teach either?

There is a difference between a non-sectarian state which welcomes all religious expressions, or none at all, and Secularism, an anti-religious approach to governance invented during the French Revolution, which seeks to discriminate against Christians. The contributions of Christianity, such as its insistence on the inviolable dignity of every human person as the Image of God, have set whole nations free. It was Christians organizing peacefully in groups like Solidarity that helped bring down the Berlin Wall. Christianity taught the world that slavery is wrong and genocides cannot be justified. It must and will not be silenced by political hacks or tax wonks.

The church must be free to speak from her pulpits and in the public square. The Johnson Amendment is a gag order backed by the guns and jails of the state, which threatens that churches which step out of line will have their savings confiscated and their leaders crippled by fines. As a member of the Catholic Clergy and a constitutional lawyer, I have seen this Amendment abused. In the hands of a president like Hillary Clinton it would be even more dangerous.