Many have adopted this accusation as the main complaint of hindrance to believing in evangelical Christianity. There is no other concept of God attacked more than this subject. There are many things about God that are not understood immediately, I've heard the same for predestination. I’ve heard it said "people don’t join the Evangelical church because they can’t understand the teaching on the Trinity".
This is just one of many straw man arguments. People do not come to Christ because they don’t understand the numerous doctrines. They refuse to because they cannot admit they are sinful and are in need of help outside themselves. Turning over their control to God is an act of faith. Instead faith is substituted with the carnal mind wanting to understand something from strictly a human perspective.
