If you know the Truth (Ḥaqq), you affirm Him. The Truth shows you that, along with the outward obligations (farḍ), there is also an inner obligation (farḍ al-bāṭin) for the sake of Allah's riḍā (contentment with God's decree). This consists of the rectification of secrets, the alignment of will, the correctness of intention,
the supervision (murāqaba) of thought, the purification of the qalb (the heart) from everything Allah dislikes, and feeling remorse for all things that defile the qalb and the limbs (attitudes and behaviors) by committing what Allah has forbidden. (Adāb, 59)