Just 16% of self-identifying Christians believe in the Trinity, the Father, the Son and the Holy Ghost being the tri-equal, tri-eternal beings comprising one God.
That number rises to only 24 percent of theologically defined born-again Christians, and only 62 percent of born-again Christians who have incorporated their faith into every aspect of their lives.
George Barna of the Cultural Research Center at Arizona Christian University calls them "Integrated Disciples," and he says the evangelical church's marginalizing the role of the Holy Spirit is part of the answer.
“How much teaching do most Christians get exposed to about the Holy Spirit? Does the Holy Spirit exist? What's the nature of the Holy Spirit? What's the role of the Holy Spirit? There's not much of that teaching that takes place these days,” Barna said.
He says an incomplete understanding of the Holy Spirit is the mark of someone who needs to spend more time in the Word.
“I think the way that a person reacts to or responds to or understands the Holy Spirit speaks to, No. 1, how much time we spend in the Scriptures.”

Barna says preachers should preach more on the Holy Spirit and should emphasize the Doctrine of the Trinity. But it's the most basic and fundamental duties of the Christian that can help us put the Holy Spirit into a proper perspective.
“One of the simplest and quickest way to get there is for us to think about how we pray. When we pray, often we will invite God the Father, we'll invite Jesus our Savior, but how often do we invite the Holy Spirit, our advocate, our source of power, our personal guide, to participate in our daily decisions.”