Every now and then someone contacts us at Americans United and, in a very “gotcha” tone, informs us that the literal phrase “separation of church and state” isn’t in the Constitution.

These people amuse me. Do they think that, for the past 72 years, no one on the staff of an organization named Americans United for Separation of Church and State bothered to actually read the First Amendment that we work so hard to protect?

All of us here at AU are well versed in what the Constitution says about religious freedom. We’ve also read up on what our Founding Fathers and the U.S. Supreme Court have said about religious freedom – and I can promise you, both the framers and the high court have a long history of using the phrase “separation of church and state” to describe the meaning and the intent of the Constitution’s religious freedom clauses.

This month marks the anniversaries of two of the earliest references to the wall of separation between church and state. Thomas Jefferson – who drafted the Virginia Statute for Religious Freedom that became the basis for the First Amendment – is first known to have used the phrase in a Jan. 1, 1802, letter early in his presidency.

Jefferson was responding to a group of Connecticut Baptists who lamented that their state constitution and laws gave preferential treatment to certain religious denominations and made clear others were merely tolerated: “…what religious privileges we enjoy … [are] favors granted, and not as inalienable rights: and these favors we receive at the expence of such degrading acknowledgements as are inconsistant with the rights of freemen.”

Jefferson responded by touting the religious freedom rights granted in the U.S. Constitution: “I contemplate with sovereign reverence that act of the whole American people which declared that their legislature should ‘make no law respecting an establishment of religion, or prohibiting the free exercise thereof,’ thus building a wall of separation between Church & State.”

Seventy-seven years later almost to the day, U.S. Supreme Court Chief Justice Morrison R. Waite quoted Jefferson’s letter and the wall metaphor in an 1879 religious freedom case. Waite wrote about Jefferson and the metaphor: “Coming as this does from an acknowledged leader of the advocates of the measure, it may be accepted almost as an authoritative declaration of the scope and effect of the [First] amendment thus secured.”

This month marks the 140th anniversary of Waite’s majority opinion in Reynolds v. United States, but that wasn’t the last time the Supreme Court used the church-state wall metaphor. It also came up in the 1947 Everson v. Board of Education opinion involving transportation of children to private religious schools. And Justice John Paul Stevens also referenced the wall in his 2002 dissent in the Zelman v. Simmons-Harris case involving private school vouchers: “Whenever we remove a brick from the wall that was designed to separate religion and government, we increase the risk of religious strife and weaken the foundation of our democracy.”

So, while the literal words “wall of separation between church and state” don’t appear in the Constitution, the concept of church-state separation certainly does. If you doubt that, just read the writings of Jefferson, James Madison and generations of U.S. Supreme Court justices tasked with interpreting and applying the Constitution.

We’re gonna take their word for it.