Your use of the phrase "true believer" belies the fallacy of your argument. Someone calling their own self a "true believer," even an entire movement claiming some adherence to some belief system and calling someone or some group "true believer(s)" does not make them true believers.
Many have come in the name of Jesus Christ claiming to be "true believers," but if one looks at the actions and fruits of many of those, one understands that they follow neither the precepts nor the spirit of biblical Christianity. Jim Jones claimed foundations in the historical Christianity, but any idiot can look at his acts and compare them to the acts of Jesus and of the early church and see that he had no relation to those.
Matthew 7:16-20 quotes Jesus as saying, "You will recognize them by their fruits. Are grapes gathered from thornbushes, or figs from thistles? So, every healthy tree bears good fruit, but the diseased tree bears bad fruit. A healthy tree cannot bear bad fruit, nor can a diseased tree bear good fruit. Every tree that does not bear good fruit is cut down and thrown into the fire. Thus you will recognize them by their fruits."
See, you are trying to judge by words and claims. Jesus says to look beyond claims and words to the actual fruit of the lives. Do they represent the spirit and deeds of the system they claim to follow?
Christ said, "I came to give life, and to give it more abundantly." John 10:7-11 is clear on this account:
So Jesus again said to them, “Truly, truly, I say to you, I am the door of the sheep. All who came before me are thieves and robbers, but the sheep did not listen to them. am the door. If anyone enters by me, he will be saved and will go in and out and find pasture. The thief comes only to steal and kill and destroy. I came that they may have life and have it abundantly. I am the good shepherd. The good shepherd lays down his life for the sheep.
So, that is the question: Do the acts and fruit of those who claim to be true believers lead to life more abundantly, or death, pillage and destruction. That is the test, not what people claim. Words have very little value.
I'm just sick and tired of "True Believers". They fear no consequences as they're right, dontcha know? Obama is a True Believer. So is Gates, and the rest of that crowd. So was Billy Graham, someone who spouted hatred for anything other than his true belief. No thank you.