God could not possibly have intended that reason should be the faculty to lead us to faith, for faith cannot hang indefinitely in suspense while reason cautiously weighs and reweighs arguments. The Scriptures teach, on the contrary, that the way to God is by means of the heart, not by means of the intellect.
When a person refuses to come to Christ, it is never just because of lack of evidence or because of intellectual difficulties: at root, he refuses to come because he willingly ignores and rejects the drawing of God’s Spirit on his heart. unbelief is at root a spiritual, not an intellectual, problem. Sometimes an unbeliever will throw up an intellectual smoke screen so that he can avoid personal, existential involvement with the gospel. In such a case, further argumentation may be futile and counterproductive, and we need to be sensitive to moments when apologetics is and is not appropriate.