Satan was cast from heaven and is free to roam the earth with the other fallen angels, now demons.
He is limited to Earth and hell.
He knows quite a bit but is not all knowing.
If he were all knowing he would know he does not stand a chance against God now or in the end!
He is such a sneak and liar that he decieves himself!
He knows enough to temp us with our weaknesses.
Satan can tempt all he wants but cannot touch the blood of Christ and remember, he trembles at the name of Jesus; the Bible says so~