Republican Kentucky Governor Matt Bevin signed a bill allowing his state's public schools to teach classes based on the Bible: BRENDAN SMIALOWSKI/AFP/Getty Images

Kentucky has signed a law allowing public, state-funded schools to teach courses on the Bible.

Governor Matt Bevin participated in the bill signing ceremony in the state capitol building which opened with a Christian prayer.

State Representative DJ Johnson said the Bible “really did set the foundation that our founding fathers used to develop documents like the Declaration of Independence, the Constitution, the Bill of Rights,” local news station WDRB-TV reported.

The class would be an elective, not a requirement for students and each local school board has the option to offer the class or not.

Mr Bevin was perplexed as to why this would not be presented as an option for Kentucky students, adding “I don't know why every state would not embrace this, why we as a nation would not embrace this”.

The US Constitution’s clause on separation of church and state is the reason, according to critics like the American Civil Liberties Union (ACLU) of Kentucky.

“We want to make sure that teachers can teach and make sure that they don't go in to preach,” ACLU Advocacy Director Kate Miller told WDRB-TV.

Though Mr Johnson noted that the development of the course would not be unconstitutional, the state Department of Education will be the agency helping school districts develop the curriculum.

The department, like every state education department in the country, receives federal government funds.

Recently, in a related case the US Supreme Court ruled in favour of a church in Missouri which had sought state funds to fix the pavement of its preschool playground. The court said the state cannot deny religious institutions any public benefits.

Mr Bevin noted that: “You could be an atheist, and you would appreciate there's a lot of wisdom in the Bible”.

No other religious texts are included in the bill, which is set to go into effect on 30 June.