An apostate's defection from the faith may be intellectual, as in the case of Ernst Haeckel, who, because of his materialistic philosophy, publicly and formally renounced Christianity and the church. Then, there is Dr. Bart D. Ehrman who has rejected Christ because of his doubt in the trustworthiness of the Bible and the problem of evil, and so he has actively worked in opposition to Christ for 20+ years. It may also be moral and spiritual, as with Judas, who for filthy silver pieces basely betrayed his Lord.