Sufi Heresy: Nothing Exists Except Allah

The Sufi leader Abou Hamed al-Ghazzali writes in his book Mishkat ul Anwar:

فإذن لا إله إلا الله توحيد العوام و لا إله إلا هو توحيد الخواص

"La elaha illa Allah (there is none worthy of worship except Allah) is the Tawheed of the commoners, and La elaha illa Huwa is the Tawheed of the elite."

Reference: Mishkat ul Anwar, page #60

He further writes:

ليس في الوجود إلا الله
"There is no existence apart from Allah"

فإذن لا موجود إلا الله تعالى و وجهه
"There is no existence except Allah Most High and His Face"

Reference: Mishkat ul Anwar page #55-56