At least four Presbyterian churches in the state of Missouri have received threats in response to the Presbyterian Church (USA)'s decision to embrace same-sex marriages.

Over 170 churches affiliated with the Presbyterian Church (USA), voted last month to change the wording of the denomination's constitution to allow same-sex marriages.

The new constitution now defines marriages as a commitment "between two people, traditionally a man and a woman."

The amendment will take effect this summer.

According to the St. Louis Post-Dispatch, the First Presbyterian Church and the Westminster Presbyterian Church in Cape Girardeau, First Presbyterian Church in Jackson and First Presbyterian Church in Perryville received anonymous letters that threatened their congregations in response to the Presbyterian Church (USA)'s decision.

The Dispatch said that the anonymous letters cite Scripture, prophesised that the churches would burn, and that pastors would be fired because of the change.

One Presbyterian leader expressed concern for the four churches, and condemned the threats as inconsistent with the teachings of Christianity.

"I was grieved and fearful for our pastors and churches," Anita Hendrix, leader of the Giddings-Lovejoy Presbytery told the Dispatch. 

"I think this is not the way to deal with disagreement ... It's obviously someone who is not acting in a way that is consistent with what I would see as Christian values." 

Hendrix asked for prayers for the safety of the four churces, as well as prayers for the anonymous author of the threatening letters.

"I just ask for people to pray for our churches and pray for the person who sent these letters that God might work in his or her life," Hendrix said.