ATHEISTS DO NOT EXIST BECAUSE THEY POSSESS A CONCEPT OF GOD. The Irony That To Be An Atheist One Has To Have A Concept Of God Before His Existence Can Be Denied Suggests That No Person Really Can Be An Atheist. Atheists then are people who do not want to acknowledge the truth and prefer to be ostriches that put their head in the ground.

My religion teacher said that there are no atheists because in order to reject God you must first have a concept of God and if you have a concept of God you are not an atheist. In what way is this true, if at all? Why?

This seems like utter nonsense to me, as what you're really doing is redefining the word atheism in order so that nobody is an atheist. Everybody knows that an atheist is somebody who doesn't believe in god. Is this some philosophical idea that I am not aware of? That atheist means 'without god' in the sense of 'without the concept of god' rather than the usual sense of 'without belief in god'.

Is he technically right? Is he confused?
Or is he just giving another interpretation of the word 'atheism'?

Happy Riches answer requested by Anonymous

People claim that because they do not know that unicorns ever existed, they know that unicorns never existed. While that may be so, however, prove that unicorns have never existed.

Those who possess intellects that are so superficial to believe that because they do not have evidence of a unicorn ever existing, this means that they could not have existed, demonstrate the foolishness of their arguments, and why the Bible calls people fools who do not believe that there is a Creator of the Universe capable of judging them, because they think they are so knowledgeable and wise, even though they possess infinitesimal minds.

A genuine thinker steps outside of the indoctrination of culture and questions those who indoctrinate, as the thinker seeks the truth for existence; rather than trusting mere mortals that deceive themselves because they are repeating what other people assert is true after having said “we believe’ or “It maybe’’, or using some conditional phrase to preface their statement; before they start indoctrinating the gullible that what they say is fact.

Definition is what determines the means of conceptualization. Your religion teacher is right therefore to say that unless a person has not got a concept of God the Creator, the concept that the Creator God exists cannot be rejected.

Atheism is the rejection of the Creator. But when you give thought to what atheists claim regarding existence, it is science fiction extended beyond comprehension and requires a massive rejection of reality, and a requirement to believe that the infinitesimal mind of man is capable of understanding all that is contained within infinity. Only the gullible fall for it. The same as the gullible believe politicians create foundations to help and serve the impoverished.

Those Who Seek The Truth Upturn Every Stone To See What Lies Beneath, Just In Case