i see you have said that "taken out of context" means "i dont wanna change my mind"
this is false. there are situations in which people do in fact take things out of context. it happens when someone assumes they understand the meaning of a text just by reading it on the surface level, isolated from the rest of scripture
in a sense, you are choosing to hold on to the assumption that this one section of scripture "he cannot commit sin" , means that a Christian can never submit themselves to sin
i would have to say that maybe you yourself are the one who chooses not to ponder whether your interpretaion is flawed
1st john also says that whoever believes Jesus is the Christ is born of God, however this doesnt mean that everyone who says a quick prayer and "believes" is born again. there is more than just what is on the surface. we must interpret scripture with scripture
yes there is a sense in which a christian cannot commit sin, justa as there is a sense in which we should pluck out our eye if it causes us to sin, but we must interpret scripture with scripture. your interpretation cannot reject other scriptures and concepts taught in the bible.
i dont think your interpretation is way off but it seems perhaps slightly off