God speaks to the world in the language of facts. God's love is good news, God's grace is good news, and His grace and love are His power for salvation to all those who go on believing. Guilt is gone by the grace of God. Paul does not say that you cannot understand the things of God. Man loves darkness rather than light.
Man rejects truth rather than lies.
Man does not want to see and hear and know because he can be held accountable for acting in accord with what he sees and hears and knows. In this manner man attempts to make a bulwark of his ignorance and a virtue out of his refusal to know. No appeal to hereditary defects avails, no pleas that you are crippled by being deprived of a cultural milieu in which you would otherwise be good avails. No, it is man who is at fault, not heredity and environment, though these do play their parts. But they are not man's scapegoats, and this to man is a tragedy.