The Rev. Paul Brooks, pastor of First Baptist Raytown, Mo., who has been involved in interfaith work, said the survey results were "disheartening to say the least.
"Clearly evangelicals have dropped the ball when it comes to teaching the Bible and related information," he said.
"It is as if we have done 'nothing in particular' to teach and train our congregations. I guess we should congratulate our Jewish and Mormon friends for doing a better job than we do. At least we did do somewhat better answering questions about Christianity itself."
Brooks said he teaches about other faiths.
"I think all churches should. It teaches respect for others and helps church members better understand Christianity."
The Rev. Gail Greenwell, rector at St. Michael & All Angels Episcopal Church in Mission, Kan., read the entire 70-plus-page study. She said she was not surprised by the relatively low ranking of white mainline Protestants.
"Many people identify themselves as Christians, and they may identify with a particular denomination, but that doesn't necessarily translate into active Christian education and discipleship as a lifelong process," she said.
"The Episcopal Church is open to studying world religions," she said. "Some denominations may feel the study of world religions denigrates the unique salvation available in Jesus Christ.
"We need to do a better job in making Christian education a lifelong journey. We have to study our church traditions, the Bible and how God is working in this world around us.
"In short, the survey shows that we have a lot of work to do."