When aware of yourself being mindful you are no longer mindful

When someone begin to be mindful, that is fine but as they are aware themselves they are mindful and say "I'm mindful", one already lost one's mindfulness as they are focus on themselves being mindful instead of really being mindful of one's experience. Conceptual and language mind prevent one's being mindful of one's true experience. It's a trap.

A small false thought can obstruct our vast great enlightened nature

Our enlightened nature is so vast and great, but a small drop of false thoughts or afflictions can obstruct us from our vast and great enlightened nature

Trying to be the most sincere person is not sincerity

Those who try to be the most sincere than others are not sincere as their mind are contending and competing to be better than others. Sincere is one mind and has not space for other afflictions including being contentious, arrogant or full of self.