[1:3] The Compassionate, the Merciful
Both names are derived from mercy (raḥma). Mercy is an eternal attribute and it is the [divine] desire for blessing (irāda al-niʿma). According to the experts (ahl al-taḥqīq), these are two nouns denoting intensification with no distinction between the two [in terms of the recipients of the mercy].
It is said the compassionate (al-raḥmān) is the more emphatic and more complete in expressiveness. Nothing other than the Real (s) is called raḥmān without restriction, while the merciful (al-raḥīm) can be used to describe others. By means of His mercy the servant comes to know that He is the Compassionate. If not for His mercy no one would know that He is the Compassionate. Whether mercy is the desire for blessing or the blessing itself, as some would have it, the blessings themselves are varied and their degrees are different, for one blessing is a blessing for bodily forms (ashbāḥ) and outward circumstances (ẓawāhir) and the other blessing is a blessing for spirits (arwāḥ) and inner secrets of the heart (sarāÌir).
In the system of those who distinguish between the two, the Compassionate (raḥmān) is a specific term with a general meaning, while the Merciful (raḥīm) is a general term with a specific meaning: As the Compassionate, He provides comfort for all people in their external circumstances while the Merciful grants success to the believers for the life of the inner secrets of their hearts (sarāÌir). He is the Compassionate by that which He gives in comfort (rawwaḥa) and the Merciful by that which He gives in glimmers (lawwaḥa). Giving comfort (tarwīḥ) is through acts of beneficence (mabārr) and the giving of glimmers (talwīḥ) is through lights (anwār). The Compassionate is with the unveiling of His manifestation (tajallī) while the Merciful is with the kindness of His being a friend and protector (tawallī). The Compassionate is with what He gives in faith (īmān) and the Merciful is with what He confers in knowledge (ʿirfān). Or the Compassionate is with what He grants in knowledge (ʿirfān) and the Merciful is with what He undertakes in forgiveness (ghufrān). Or the Compassionate is with what He gives in blessing in forgiveness (ghufrān) and the Merciful is with what He bestows in good pleasure (ri?wān). Or the Compassionate is with what He honors in good pleasure and the Merciful is with what He gives in blessing in vision and eyewitnessing (ʿiyān). Or the Compassionate is with the success He gives and the Merciful is with what has been realized. Granting success (tawfīq) is for transactions and behaviors (muʿāmalāt) while realization (taḥqīq) is for intimate communications (muwāṣalāt). The transactions and behaviors are for those who seek (qāṣidūn) and the intimate communications are for those who find (wājidūn). The Compassionate is with what He bestows as a favor for them and the Merciful is with what He deflects from them, for the bestowal of favors (ṣanʿ) is beautiful caretaking (riʿāya) and the defending (dafʿ) is the best solicitude (ʿināya).