This simple sentence is one that is most easily overlooked. Because it is self-referencing.
One must slow down to first hear it. Then one must be willing to investigate thoroughly.
Who is looking out of you?
This is where it is easily overlooked, because if you just say I am... though that maybe a true statement, It isn't if you have just assumed you know who you are.
Come back slowly to who is looking out of you. Look to see who is there.
The silent/Still Observer is You. You are Aware of itself.