The Four Levels of Purification
The First: Purifying your physical appearance from impurities [such as defecation and urine], unclean things [such as excretions from the nostrils] and from having contact with impurities.
The Second: Purifying your limbs from committing sins.
The Third: Purifying your heart from bad mannerisms and abhorrent behavior.
The Fourth: Purifying your inner self from anything other than Allaah the Exalted [i.e Monotheism], and this is the upmost objective.
Whoever's foresight is strong would turn to this objective, and whoever's foresight is blinded would not understand except the first of these four levels. You would see him waste a lot of his precious time in excessively cleaning his nostrils or washing his clothes, believing that this is the only thing required from purification, due to lack of knowledge, listening to the whisperings [of Shaytaan] and ignorance of the ways of those of old, those who used to spend their time in purifying their hearts and were more negligent of their outward appearance…
…the affair has reached the point of a people called ‘ the foolish purifiers', you see them spending most of their time purifying their physical appearance, while internally they are rotten, filled with the impurities of pride, conceitedness, ignorance, hypocrisy and boastfulness. If they were to see someone practicing Istijmaar with rocks, walking bear footed, praying on the floor without a mat, or performing Wudoo from an old person's vessel, they would criticize him severely, label him with impure descriptions and would avoid eating his food.
So look at how they turned a person who dresses humbly – which is from Eemaan, into being unclean, and foolishness into purity. The turned ‘Munkar' into ‘Ma'roof' and ‘Ma'roof' into ‘Munkar'.
However, whoever intends with his outward purification to be clean, and does not excessively waste water and does not believe that using a lot of water is from the religion, then this is not ‘Munkar' rather it is a good to do so.
Whoever would like to know more about purification should refer to the books of Fiqh, for what is intended by this book is the clarification of mannerisms.
Ahmad ibn ‘Abdur Rahmaan al-Maqdisee
Mukhtasar Minhaaj al Qaasideen : P. 31