Indeed, I am inclined to think that the theistic arguments do provide some non-coercive, evidence of God's existence. By non-coercive, I mean that the theistic arguments aren't of such power and illumination that they should be expected to persuade all rational creatures. Rational people can rationally reject the theistic proofs. Nonetheless, I believe that someone could rationally believe in God on the basis of theistic arguments, but no one must. I also believe, like Calvin, that the natural knowledge of himself that God has implanted within us has been overlaid by sin.
Redemption includes the gradual removal of the effects of sin on our minds.
Attention to theistic arguments might do that. The primary obstacle to belief in God is moral rather than intellectual. On the mountain one may feel one's smallness in relation to the grandness of it all. The sermon may convict one of sin. The loss of a job or a divorce may reveal one's unjustified pride.