@Aaron Yost I think that the majority of cases are a heart issue at the core. But, there are some exceptions, there are certain teachings in Christianity that are hard to intellectually wrap your head around and it takes awhile for the mind settle. Take the Trinity for example, there comes a point when you just have to settle on the understanding that you have and move on because human intellect can only go so far on a subject like that. And I think most Christians, especially those who grew up in church, do not realize how much loads and loads of information there is to comb through for a new believer or a seeker. There are some things that don't need to be settled or reasoned out in the mind right away, sometimes the understanding comes as you move deeper in the Christian experience. Sometimes the Holy Spirit just lets a light bulb go off in your head and you cross over that intellectual barrier in an instant, the very thing you were trying to do for years. (This is especially encouraging for those of us who have felt mental blocks and think to ourselves, "How can these people believe all this stuff, no questions asked? Or how are they so comfortable in something they used to be skeptical about and meticulously questioning?") Some people want to believe and their heart is in the right place, but cannot get over an intellectual wall that seems to be blocking them. This is when they can pray the prayer, "I believe, help thou my unbelief." (Doubting Thomas type of stuff)