As a result of our sinful human nature, there can be no unmediated relationship between God and humanity, for God must wear a mask in all of his dealings with people. Moreover, human nature cannot recognize God, nor comprehend his nature, without a covering. Therefore God, in his grace and mercy, envelops himself in his word and works and reveals himself in certain forms. These concrete forms of the Holy Spirit are God's way to people and a rejection of every way from humanity to God; they are the universal epiphanies for all people.
As God comes to reveal his fatherly heart and will, he deals with people in a twofold manner: first outwardly, through the oral word and material signs; then inwardly, through the work of the Holy Spirit and faith. God could have saved the human race in another way, but it was his will to save us, and to reveal himself, in this way. Accordingly, it is the responsibility of humanity to apprehend God where and how he has chosen to reveal himself - through the will of his good pleasure and the will of the sign - so that every person might find and worship the true God, experience salvation, and receive eternal life.