There are 99 beautiful names of Allah Almighty among which AL-RAHMAN and AL-RAHEEM are the two beautiful names. These two names are exclusive names of ALLAH. Both these names are Originated from the same root word i.e. RAA HAA MEEM. These words are derived from the Arabic language.
In Arabic, RAA HAA MEEM stands in the meaning of Womb (in Arabic Raham). Though the Arabic language is very vast language. One root word is related with different meanings, the word Rahmah is also related to this root word and both words Al-Rahman and Al-Raheem are derived from this word.
In Arabic Tafseer, the word Raham which means womb also explain the mother’s love. As a mother loves her child unconditionally similarly Allah loves his creation infinitely. All of us while praying Salah recite these two words Al-Rahman, Al-Raheem many times, do we really understand the difference between two?
First I will describe AL-RAHMAN, this name is used only for Allah Almighty. Rahmah means mercy. Al-Rahman is the most powerful name of Allah which means vast mercy of Allah upon his creations. This word has been used in the Holy Quran by Allah S.W.T. to show His kindness for all beings.
Whenever a person is in sorrow or difficult situation, this nature of his Creator strengthens his will. Allah S.W.T is Al-Rahman His mercy is for all the living beings, human beings whether they are Muslims or non-Muslims.
In The Holy Quran, Allah S.W.T reminds the humans about His blessings and Bounties He has showered upon us describing Himself as Al-Rahman, in Sura Rahman. Allah’s mercy is vast and is understood by its name AL-RAHMAN. It is due to his mercy a cruel animal take care its child rather killing it.
Abu Hurairah narrated that the Messenger of Allah (ﷺ) said: “Allah created a hundred mercies, and He placed one mercy among his creation, they show mercy to one another by it, and there are ninety-nine mercies with Allah.” Jami` at-Tirmidhi 3541
AL-RAHEEM is also the name used only for Allah Almighty. Meaning of Al-Raheem stands for the mercy that embraces all the creations of Allah. Al-Rahman refers to the vastness of Allah’s mercy, and al-Raheem refers to its effect on His creation
In The Holy Quran, the word AL-RAHEEM is used several times for his believers. Al-Raheem means to bestow mercy on his creations now and the hereafter. However, everything is the creation of Allah. We believe in Allah and believe that he is Al-Rahman and Al-Raheem.
Many scholars say that the word Al-Raheem is just used for the mercy of Allah that He will attribute only to his believers. Whereas Al-Rahman is used in the meaning of mercy that Allah will shower on all his creations i.e. jinn, human beings, animals, plants and every living and non-living thing.