There has been an enormous backlash from Indiana's decision to enact a law that would allow businesses to discriminate if they invoke religious liberty. Responding to a flurry of boycott threats, Republican Governor Mike Pence signed a “fix” to the bill he says would prevent it from being used to discriminate.

But for the religious right, the battle lines have been drawn. 2016 presidential contenders like Jeb Bush, Marco Rubio, Bobby Jindal, Rick Santorum, Ben Carson and others have all rushed to defend Indiana's legislation, as a number of state legislatures continue to debate enacting similar measures. In Louisiana, one Republican lawmaker is introducing a narrower bill specifically taking aim at marriage, with the intent to allow businesses to discriminate against same-sex weddings and deny benefits to employees in same-sex marriages.

In all of these examples, religious belief is invoked to justify a right to discriminate. Proponents argue that constitutional protections for religious freedom are insufficient, and these new laws—aimed at granting businesses themselves exemptions from laws based on the invocation of religion—are necessary. It's no surprise that these laws are proliferating around the same time marriage equality is slowly becoming the law of the land in most of the country. However, cries of religious liberty and a religious-based right to discriminatory and harmful behavior are not new. For centuries, religion has been used and abused as a shield for harmful behavior, to justify everything from slavery to sexist violence to racism in the Jim Crow South.

Slavery's Religious Supporters

In today's history books, the righteous deeds of abolitionists—many of them devout Christians—are rightly documented, showing how the Gospel was used to liberate millions of human beings who had been subjugated by slavery. However, while the abolitionists did use scripture to make their case, many of their pro-slavery opponents also invoked biblical traditions.

In 1852, the writer Josiah Priest published a book titled Bible Defence Of Slavery: And Origin, Fortunes, and History of the Negro Race. The publisher's preface points out the belief that “the institution of slavery received the sanction of the Almighty in the Patriarchal age; that it was incorporated into the only national constitution which ever emanated from God, that its legality was recognized, and its relative duties relegated by our Saviour, when upon earth."

Priest quotes liberally from scripture, citing numerous examples of enslavement being sanctified in the Bible. He writes, “If God appointed the race of Ham judicially to slavery, and it were a heinous sin to enslave one, or all the race, how then is the appointment of God to go into effect? …. God does never sanction sin, nor call for the commission of moral evil to forward any of his purposes; wherefre we come to the conclusion, that is is not sinful to enslave the negro race, providing it is done in a tender, fatherly and thoughtful manner.”

Priest's interpretations of the Bible were particularly popular in the American South, with the Southern Baptists championing religious justifications for enslavement. Prominent Baptist minister Richard Furman helped polarize southern white Baptists to support the institution of slavery; he wrote to the governor of South Carolina explaining that “the right of holding slaves is clearly established in the Holy Scriptures”; he specifically cites the “Israelites [being] directed to purchase their bond-men and bond-maids of the Heathen nations; except they were of the Canaanites, for these were to be destroyed. And it is declared that the persons purchased were to be their 'bond-men forever;' and an 'inheritance for them and their children.'”

It was not until 1995's Southern Baptist Convention that the organization issued an apology for its former stance on slavery.

Weaponizing the Bible For Sexism

The Seneca Falls Woman's Rights Convention of 1848 was one of the major gatherings of the women's movement, and is considered to have been one of the turning points for suffragists in particular. In the Declaration of Sentiments and Resolutions the activists there compiled, they specifically included a provision condemning those who would use the Bible to suppress their rights: “Resolved, That woman has too long rested satisfied in the circumscribed limits which corrupt customs and a perverted application of the Scriptures have marked out for her, and that it is time she should move in the enlarged sphere which her great Creator has assigned her.”

Clinging to verses in the Bible that gave unequal status to men and women, opponents of the suffragists justified their beliefs with religious teaching. “Who demand the ballot for woman? They are not the lovers of God, nor are they believers in Christ, as a class. There may be exceptions, but the majority prefer an infidel's cheer to the favor of God and the love of the Christian community. It is because of this tendency that the majority of those who contend for the ballot for woman cut loose from the legislation of Heaven, from the enjoyments of home, and drift to infidelity and ruin,” intoned Justin Fulton, a prominent reverend in 1869.

The religious-based bigotry against women was so intense that Elizabeth Cady Stanton actually wrote The Woman's Bible to directly challenge religious oppression of women. The book's critique of using religion to justify discrimination against women was considered so controversial it not only was denounced by sexists, but also by the National American Woman Suffrage Association, which saw the book as a mistake for the movement.

Jim Crow's Holy Defenders

Other than the Christian right's modern-day campaign against gay rights, the most recent use of scripture and religious liberty to justify discrimination was the 20th-century defense of Jim Crow. ThinkProgress's Ian Milhiser notes that Democratic Senator Theodore Bilbo used his religious faith to justify preventing integration of the races.

“[P]urity of race is a gift of God…. And God, in his infinite wisdom, has so ordained it that when man destroys his racial purity, it can never be redeemed,” wrote Bilbo in the book Take Your Choice: Separation or Mongrelization.

Segregationist governor George Wallace invoked God 27 times in his famous speech that came to be known as “segregation now, segregation forever.” Georgia governor Allen Candler said that “God made them negroes and we cannot by education make them white folks”; following the landmark Brown v. Board of Education case that mandated desgregation of schools, Senator Harry Byrd took to the floor and quoted Genesis and Leviticus to justify continued segregation of the races.

Harming Church and State

None of this is to argue that religious values can't inspire individuals to do good. Towering figures such as the Reverend Martin Luther King, Jr. and Mother Teresa improved the lives of millions and used scripture to liberate people, not oppress them. But a cursory review of the history shows that invoking religious preference to justify discrimination and oppression is a common tool. That's why although the Constitution guarantees your right to practice your religion as you see fit, it also prevents the government from using it to deny people rights. The current debates over religious liberty are hardly new, they are simply new cover for using religion to deny people rights, an old routine that harms both the church and the state.