Dr Abdul Hai Arfi has stated that:
These are four a’mal (actions) and these four are the core of Shar’iah and Tariqah, and are so easy that to practice on them does not cost money, time or effort. The person who makes these four things a habit will develop a special link with Allah Most High.
He will experience its benefits during his life and the heart will be conducive towards islah (reformation). Eventually he will reach such a stage that even if he wishes to commit sin, he will be unable to do so.
The four a’mal are:
Istighfar (seeking repentance)
Isti’adhah (seeking refuge)