Sceptic
SCEP'TIC, noun [Gr. from to look about, to consider, to speculate. See Show.]
1. One who doubts the truth and reality of any principle or system of principles or doctrines. In philosophy, a Pyrrhonist or follower of Pyrrho, the founder of a sect of sceptical philosophers, who maintained that no certain inferences can be drawn from the reports of the senses, and who therefore doubted of every thing.
2. In theology, a person who doubts the existence and perfections of God, or the truth of revelation; one who disbelieves the divine original of the christian religion.
Suffer not your faith to be shaken by the sophistries of sceptics.