[This is part of the text of an article I wrote for St. Francis Magazine which can be found HERE. Part I can be found HERE.--AD]
[...]Take a look at the pillars of Islam. While Muslims do not use the language of sacrament, they certainly have the concept, though in an incomplete manner. (For ultimately the fullness of the sacramentality of Creation cannot be grasped without the incarnation). Because the sacramental principle is distorted but present in Islam, one ends up with the rather crude and instrumentalist language regarding forgiveness of sins: that if one does this or that then certain sins will be forgiven. Forgiveness in Islam is not the reconciliation of mercy and justice as it is in Christianity: it tends more towards a sort of randomness and, some might say, capriciousness on the part of Allah. The two are related of course. Because there is no reconciliation of justice and mercy in a body—a human body which is “sacrificed for us” and “takes away the sins of the world”—there can be nothing higher than capriciousness which oscillates between mercy and justice without really dealing with either of them in a concrete way.
Nevertheless Islam is filled with rituals and there can be no doubt that through these concrete rituals—and much attention is given to form—mercy and forgives can be earned, though one is seldom assured that they have been imparted. To bring a person from Islam into Christianity is to bring them from one set of signs and symbols into another. This is true even if we are using the phraseology of the Kingdom of God and Islamic vocabulary. Islam already has a ritual washing which is performed by devout Muslims quite frequently. Baptism is an alternate ritual washing, performed once.
The community of the Kingdom of God has a ritual meal which is celebrated on a regular basis by those who have made the required confession of faith (in baptism). It is not a sacrifice of a living animal, as is the Islamic ritual sacrifice-meal (Eid al Adha); also, it is performed more often (in Acts daily, and until the 16th C. weekly). The Islamic sacrificial meal is a memorial of a grand sacrifice provided by Allah whereby Abraham’s son was spared: it and the meal celebrate and recall filial obedience. The ritual sacrifice-meal among the subjects of the Kingdom is similar, but not identical. For one, it is always a participation, a going-back-to and a reliving of one sacrifice that was made at a specific point in time (under Pontius Pilate) in a specific way (he was crucified, dead, and buried) on a given hill near Zion. There too is a theme of filial obedience. In the Quran the son of Abraham knows ahead of time that his father will kill him, unlike in the Genesis narrative. Yet he goes with him to meet this fate. In a more dramatic and lengthier narrative we have a similar story in the Gospels. But the ultimate end of the sacrifice is not only obedience for the sake of obedience, but obedience for the sake of reconciling all Creation to God. Another way to put it is this: to preserve the justice and mercy of God through the sacrament of Jesus’ body. [...]
Abu Daoud. 'Mission and Sacrament, Part II' in Saint Francis Magazine 4:3, Dec. 2008