What Al-Ghazali himself thought of these speculations of the Sufis and the danger of this kind of mysticism we learn from his book: “The speculations of the Sufis may be divided into two classes: to the first category belong all the phases about love to God and union with Him, which according to them compensate for all outward works. Many of them allege that they have attained to complete oneness with God; that for them the veil has been lifted; that they have not only seen the Most High with their eyes, but have spoken with Him, and so far as to say ‘The Most High spoke thus and thus.’ They wish to imitate Hallaj, who was crucified for using such expressions, and justify themselves by quoting his saying, ‘I am the Truth.’ They also refer to Abu Yazid Bistami, who is reported to have exclaimed, ‘Praise be to me!’ instead of ‘Praise be to God!’ This kind of speculation is extremely dangerous for the common people, and it is notorious that a number of craftsmen have left their occupation to make similar assertions. Such speeches are highly popular, as they hold out to men the prospect of laying aside active work with the idea of purging the soul through mystical ecstasies and transports. The common people are not slow to claim similar rights for themselves and to catch up wild and whirling expressions. As regards the second class of Sufi speculation, it consists in the use of unintelligible phrases which by their outward apparent meaning and boldness attract attention, but which on closer inspection prove to be devoid of any real sense.”