People choose what cereal to eat everyday. It is in their physical and spiritual capacity to pour the cereal out of the box, pour milk on it and eat it. People trust friends, the media, doctors, books, and everything else everyday, as it is in their capacity as a rational, volitional soul to do so. But when they are told by God’s Word to trust Jesus Christ to save them from their sins, all of a sudden people won’t do it.
They have the facultative capacity to trust, they choose to trust all sorts of other persons and things, but they don’t want to trust Jesus. They would have to admit that they are sinful, are deserving of eternal punishment, they would have to believe things that are not popular, they would be taking a risk in casting themselves upon one largely unknown to them, and ultimately, they simply really do not like God and want to live as they please their own way (Jn. 3:19).
They have the natural capacity to believe, but mysteriously, they will not, unless their natural faculties are renewed by the Holy Spirit to love and desire that which they have the natural capacity to do. The Natural vs. Moral ability page has been greatly updated with quotes by Richard Muller, John Owen, Francis Turretin, and others.