More than one-third of self-identifying Christians in the United States say they are not familiar with the concept of tithing, and only one-fifth practice say they practice tithing, according to a new Barna survey.

The poll, released Wednesday, found that 43 percent of Christians say they are familiar with the term "tithe," while 22 percent say they're familiar but cannot recall the exact meaning, and 36 percent say they are not familiar.

About one-fifth (21 percent) of Christians practice tithing to their church or ministry, while 25 percent don't give financially, and 54 percent donate an amount less than 10 percent.

Biblically, a tithe equals 10 percent.

Meanwhile, tithing is more popular among practicing Christians - a category Barna defines as Christians who attend a religious service at least once a month and say their faith is very important in their lives. Among this group, 59 percent say they are familiar with the term "tithe," while 18 percent are familiar but cannot recall the exact meaning, and 22 percent say they are not familiar. All total, 42 percent of practicing Christians say they tithe.

Barna's analysis surmised that pastors may be the reason more Christians don't embrace tithing. Only one-third of pastors favor their congregation giving a 10 percent tithe, while 21 percent say their congregation should give enough to be considered sacrificial, and 20 percent say the congregation should give as much as they are willing.

"Church leaders and Christians may wonder whether it matters if the tithe falls out of the mainstream," the analysis said. "After all, church giving should not be reduced to an equation, and heartfelt, reverent generosity can be accomplished with or without deep knowledge of the tithe. Still, as a fundamental, scriptural idea of Christian stewardship becomes a hazy concept, it appropriately raises questions - about how modern ministries approach funding and resources, and, more importantly, about the broader culture of generosity being nurtured among Christians."

The Barna data is part of its latest release, Revisiting the Tithe and Offering.

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