"The divine Names most clearly associated with mercy and compassion are given in the formula by which every significant act in Islam is consecrated, and with which every chapter of the Koran begins (with the exception of Chapter 9), the formula known as the basmala: "In the Name of God, the Compassionate, the Merciful" (bismi'Llahi r-Rahmani r-Rahim). The two Names, al-Rahman and al-Rahim, share the same root (r-h-m), and both express rahma, the meaning of which comprises the qualities of compassion, mercy, forgiveness, loving goodness. "Call upon Allah or call upon al-Rahman," the Koran tells us, expressing the quasi-equivalence between "the Compassionate" and God as such, thereby indicating the defining characteristic or "identity" of the ineffable One, "whichever of these two (Names) you call upon, unto Him belong the most beautiful Names." (17:110).
Given the fact that among the divine Names one also finds "the Almighty," "the Avenger," and other Names expressive of divine rigor, it is of great significance that the formula of consecration contains a repetition of the theme of mercy; one might have thought it more "logical" or balanced to include a name of rigor in this definitive consecration describing the essential nature of "God" in whose name one begins everything, and this have something like: "In the Name of God, the Compassionate, the Powerful." The very fact that two Names of Mercy are given in this formula, which inaugurates the revelation and consecrates every act of significance for the Muslim, allows one to see that the essential nature of ultimate Reality is compassionate and merciful, these two qualities being expressive of the overflow of infinite love.
In the spiritual tradition of Islam, great stress is placed on love as being the fountainhead of creation. "I was a hidden treasure," God declares, "and I loved to be known, so I created the world." The Names of Mercy, al-Rahman and al-Rahim, give voice to this creative impulse of divine love, and they are both related to the word rahm, which means "womb." Here one glimpses another mystery of the all-embracing oneness of mercy: Just as the womb entirely envelops the embryo growing within it, the divine "matrix" of compassion contains and nourishes the whole corpus of existence unfolding within itself. The qualities of divine anger are not being denied in this perspective; rather, they are seen as the inevitable consequences of human sin. The latter is by definition limited and relative, so the divine qualities elicited by relativity cannot be placed on the same level as those that flow forth from the very nature of the Absolute. Thus we are told not only that "My Mercy encompasses all things" but also that "My Mercy takes precedence over My Anger." On the one hand, there is the rigorous restoration of an equilibrium ruptured by the sins of relative beings; on the other, the merciful reintegration of purified souls within the beatific nature of the Absolute.
The Koran describes the divine Mercy in a manner that is as inspiring as it is overwhelming: God's love is infinite and thus His Mercy is given to us "beyond all reckoning," beyond anything "deserved" by us; this is a key dimension of the spiritual justice of God: "Whoever comes (before God) with a good deed will receive ten like it; but whoever comes (before God) with an evil deed will only be requited with its like; and no injustice will be done to them" (6:160).
~ Excerpt from "My Mercy Encompasses All" by Reza Shah-Kazemi, pp. 5-8