Ar-Rahman and Ar-Raheem. These two names are derived from rahma (mercy). (The concept of) mercy necessitates one who is an object of mercy, for no one is an object of mercy unless he is in need. Ar-Rahman is the one by means of whom the needs of the needy persons are satisfied in such a way that neither intent, volition nor solicitude are involved. The one in need is not called Raheem.
The meanings of Ar-Rahman and Ar-Raheem by Imam Ghazali's book of names. (Maqsad al-Asna). Download the names with its meanings on a beautiful photo.