Both external (Zaahiri) and internal (Baatini) acts and duties are commanded in the Qur’aan. Thus the Qur’aan while commanding Salaat and Zakaat:
"O People of Imaan.' Establish Salaat and give Zakaat",
also commands shukr (gratefulness):
"And be grateful unto Allah".
At one place is to be found:
"Fasting has been decreed upon you."
"Upon mankind is the Hajj of the Bait for Allah.",
while at another place is to be found:
"He (Allah) loves them (Mu'mineen) and they love Him.",
"Those who have adopted Imaan are most ardent in the love of Allah."
Similarly, along with:
"When they stand for Salaat, they stand half- heartedly",
is to be found:
"They show people (i.e. they perform Salaat in Riyya)."
The Qur’aan, like it reprimands and condemns the defaulter of Salaat and Zakaat, also states the evil of pride and vanity (takabbur and ujub).
The same applies to the Ahadeeth. Like the chapters of Salaat, Sawm, Ba’y (trade and commerce), Nikaah (marriage), Talaaq (divorce) are to be found, so too do the chapters of Riyaa, takabbur, etc. exist. No Muslim can refute the fact that like the A’maal-e Zaahirah are Divine Commands so too are the A’maal-e Baatinah. “(Establish Salaat and pay Zakaat)” are positive commands just as “(Adopt sabr and shukr)” are positive commands.
Like the Aayat: “Fasting has been decreed upon you‘‘, establishes the Shar’ee nature of Fasting, the Aayat: “Those who have Imaan are the most ardent in the love of Allah”, establishes the Shar’ee nature of Love for Allah. On closer examination and reflection it will be realized that all the A’maal-e Zaahirah are designed for the reformation of the A’maal-e Baatinah. The purification of the Baatin (the heart and soul of man) is the aim and the basis of Najaat (salvation in the Aakhirat) while the despoiling of the Baatin is the cause of destruction.
Allah Ta’ala declares:
"Verily, he who has purified the nafs has attained victory, and he who has despoiled it has lost."
"That Day (of Qiyamat) neither wealth nor sons will benefit (anyone), but that person who comes to Allah with a reformed heart."
The first Aayat asserts victory as being the consequence of the purification of the Baatin while the second aayat negates the utility of wealth and sons in the absence of a reformed heart. wealth and sons in the absence of a reformed heart.
Imaan and Aqaa’id (Articles of Faith) on which pivots the acceptance of all A’maal (actions), are conditions of the heart (i.e. the Baatin). It is manifest that A’maal are designed for the perfection of Imaan. It is therefore clear that the original purpose is the reformation (Islaah) of the heart by virtue of which man is ushered into the Divine Court of Acceptance and attains the lofty spiritual ranks. This is precisely what is known technically as Tasawwuf