There are three types of fasting
One is of the average Muslim (one who submits to the Will of Allah Almighty), he fasts only from food, drink, and marital relations.
The second is the fasting of the Mu'min (believer) - he fasts from everything that is forbidden - bad language, bad thoughts, looking at bad things & listening to bad things etc.
The third and most supreme type of fasting is that of the Muhsin (one who has perfected his faith in Allah Almighty) - and this is fasting from everything other than Allah subhanahu wa ta'ala. To such a person, a Knower of Allah subhanahu wa ta'ala, nothing in the world exists besides Allah. Wherever he looks, he sees Allah swt, whenever he thinks, he thinks of Allah subhanahu wa ta'ala!
[Imam Ghazali]
