I think they are afraid to leave the comfort of their indoctrination. The knowledge that everything you have been taught is built on sinking sand and myth is hard to take.
Our intentions seem clear enough. Preach the good news, the Gospel. The single thought that we can become part of God's children, with all the benefits found in the fruits of the Spirit. Faith is all it takes. The relevant Scripture has already been posted on the thread.
But, I often think we follow a different Spirit, one without a mother always nagging!