Doubt itself, I believe, is the catalyst for atheism.

Barker is the co founder of a secular humanist religious group called 'Freedom from Religion', should be called Freedom from Christ. Barker also wrote a book that I was given the task of reviewing some time ago. Before you ask the answer is yes, I did read it. In his book, "Losing faith in faith" he says the beginning of his atheism began when he started as a preacher, became more of a liberal Christian and kept on doubting (opposite of faith) until "blam" he was an atheist. It was a quite obvious story. Most of you gave me similar stories, most recently Stan.
To make the point clear lets look at the apostles and what they, not to mention the 250 million people in 2007, had or will have to endure, the torture, arrests, be-headings and such. They were put through prosecutions, tribulation, and great turmoils. Yet they kept their Hope and honor and never wavered in their faith.
The Bible talks a great deal of doubt, as you know.
Deuteronomy 28:66 "And thy life shall hang in doubt before thee; and thou shalt fear day and night, and shalt have none assurance of thy life:"
Matthew 14:31 "And immediately Jesus stretched forth his hand, and caught him, and said unto him, O thou of little faith, wherefore didst thou doubt?"
Luke 12:29 "And seek not ye what ye shall eat, or what ye shall drink, neither be ye of doubtful mind."
Romans 14:23 "And he that doubteth is damned if he eat, because he eateth not of faith: for whatsoever is not of faith is sin."
We must not trust our own lying wickedness, or others, and make sure we are not pushing our own agendas over or replacing God's (a.k.a. denominations or false religions). The thrust of my point though, is about leaving God entirely and abandoning Him.
Faith is a strong belief in a supernatural power that control human destiny, complete confidence in a plan, a loyalty or allegiance to a cause.
Webster says:
1 a : allegiance to duty or a person : loyalty b (1) : fidelity to one's promises (2) : sincerity of intentions
2 a (1) : belief and trust in and loyalty to God (2) : belief in the traditional doctrines of a religion b (1) : firm belief in something for which there is no proof (2) : complete trust
3 : something that is believed especially with strong conviction; especially : a system of religious beliefs.
Faith, in a sense, is synonymous with loyalty and TRUST. In fact the synonyms are: confidence, trust, reliance, conviction, belief, assurance, devotion, loyalty, faithfulness, commitment, fidelity, constancy, fealty, dedication, allegiance.
To doubt God Himself or that Jesus is not Lord is so damaging that this atheism is a move from light to darkness. This is the point that 2 John 7 is clear about.

I beg all of you not to depend on, or lose faith because of, anything that mankind has done. We must have faith that God's plan is true and sound and no one will get to Heaven without Jesus as it says in His Word, the authority we should all live by.
James 1:5-8 "If any of you lack wisdom, let him ask of God, that giveth to all men liberally, and upbraideth not; and it shall be given him. But let him ask in faith, nothing wavering. For he that wavereth is like a wave of the sea driven with the wind and tossed. For let not that man think that he shall receive any thing of the Lord. A double minded man is unstable in all his ways."