The Belgic Confession, Article I (2)

What then is this subjective principle of faith? What then is this subjective principle of faith? It is the principle of regeneration implanted in the heart by the indwelling and quickening Spirit of our Lord Jesus Christ. The natural man is a fool, and as such he says in his heart, "There is no God." The divine wisdom, spoken in a mystery by the apostles of our Lord Jesus Christ, and consisting of things which "Eye hath not seen, nor ear heard, neither have entered into the heart of man,"...