I'm surprised with your willingness to look at the Greek, that you are not more careful with this interpretation. That verse simply states that those born of GOD are not doing sin, and they aren't able to be sinning (not that it is impossible for them to sin) because the spirit (seed) in them won't allow it.
Everyone born of God is not doing sin, for his seed remains in him and he is not able to be sinning, because he is born of God. 1 John 3:9
But let's take it a step further and provide the context of the next verse that clearly shows that those who are born of GOD
practice righteousness, and those of the devil don't.
By this the children of God and the children of the devil are evident: everyone who does not practice righteousness is not of God, neither is the one who does not love his brother. 1 John 3:10
The corollary to this is that those who do practice righteousness (those not doing sin in verse 9) are born of GOD.
So you have taken this sensible interpretation and turned it on its head to mean that it is impossible for those who are born of GOD to sin, simply due to a careless reading of what is written. This is how false doctrines are born.