Faith in government, spouses, science, and so forth stems from assurance from people, media reports, historical performance, logic, self-persuasion, and many other sources. Without some sort of assurance, there is no reason to believe--there is no faith.
Faith in Christ is a special kind of faith. It is often described as a gift. But God will never force anyone to believe in Him, and therefore will not force the gift of faith. So how can He increase a person's faith in Christ, if coercion is not an option?
The gift of faith in Christ must be a result of heavenly assurance. Where all other worldly assurances provide some level of surety to a conviction, the One Source of ultimate surety is God Himself. This most powerful feeling of assurance from God will not be forced on us--rather we have to ask for it. If we choose to seek it, we are promised we will receive it.
Because these assurances come from God Himself, is it any wonder that faith in Christ can be so strong? Is it any wonder that upon receiving assurance from God, a person might place more confidence in Him than in contradicting evidence from science, philosophy, public opinion, or any other source? No other source of assurance can be as convincing, because no other source even approaches the same level of power, omniscience, and charity.