It is thinking that salvation is a human action that causes all our problems. In every decade and every century of history, humans have tried to turn salvation into a human action, but the gap between us and God is far wider than we ever assumed, and here we are attempting to cross this infinite gap by purely human actions when what is needed is divine action. Think of two mountain cliffs opposite one another with nothing connecting them. There would be no way to cross unless something is constructed. This is precisely what we need in order to reach God.