He who eats poisonous berries will have poison in his system, whether he knows the berries are poisonous or not. Sin is poison. Beware also of secret sins. At the same time, the Psalmist in 19:12-13 prays to God to keep him from presumptuous, shameful sins. There is a hidden pathway between secret sins & the fall into gross sin. The unconscious sins undermine your soul & in due time, the great collapse will take place.