Islam is the only faith other than Christianity which regards Jesus and Mary in very high esteem. One is astounded to find the notable Christian intellectuals, politicians, scholars and most painfully, the Christian clergy portraying Islam and Muslims as the enemies of Christ, infidels and pagans. Conversely, many uninformed and misinformed Christians are astonished when they are told about the respect and love Muslims have for Jesus and Mary despite the doctrinal differences. The Qur’an mentions “Jesus” by name twenty five times, as the “Messiah” eleven times. He is also addresses as Jesus the son of Mary: “And We made the son of Mary and his mother a sign for mankind,..”(Qur’an;23:50).  Chapter number nineteen in Qur’an has been named after ‘Mary’, where as it is not the case in the New Testament. Qur’an grants special status by considering Christians nearest in affection to the Muslims: “You will find the most violent in enmity to the believers are the Jews and the idolaters (pagan Arabs); and nearest in affection to the believers are those who say: “We are Christians.” That is because among them there are men that are priests and monks, who do not behave arrogantly.”(Qur’an;5:82).

Doctrinal Differences :

Islam believes in strict Abrahamic monotheism, individual responsibility and accountability, where the concept of Original Sin, Son of God and Trinity does not fit in strict Islamic monotheism (Tawhid), which is even refuted by many Christians thought out its history. The history of attempts to define the mysterious concept of Trinity has been traced by Encyclopedia Britannica: By the 3rd century it was already apparent that all attempts to systematize the mystery of the divine Trinity with the theories of Neoplatonic hypostases metaphysics were unsatisfying and led to a constant series of new conflicts. The high point, upon which the basic difficulties underwent their most forceful theological and ecclesiastically political actualization, was the so-called Arian controversy. Arius belonged to the Antiochene school of theology, which placed strong emphasis upon the historicity of the man Jesus Christ. In his theological interpretation of the idea of God, Arius was interested in maintaining a formal understanding of the oneness of God. In defense of the oneness of God, he was obliged to dispute the sameness of essence of the Son and the Holy Spirit with God the Father, as stressed by the theologians of the Neoplatonically influenced Alexandrian school. From the outset, the controversy between both parties took place upon the common basis of the Neoplatonic concept of substance, which was foreign to the New Testament itself. It is no wonder that the continuation of the dispute on the basis of the metaphysics of substance likewise led to concepts that have no foundation in the New Testament–such as the question of the sameness of essence (homoousia) or similarity of essence (homoiousia) of the divine persons.

The basic concern of Arius was and remained disputing the oneness of essence of the Son and the Holy Spirit with God the Father, in order to preserve the oneness of God. The Son, thus, became a “second God, under God the Father” i.e., he is God only in a figurative sense, for he belongs on the side of the creatures, even if at their highest summit. Here Arius joined an older tradition of Christology, which had already played a role in Rome in the early 2nd century–namely, the so-called angel-Christology. The descent of the Son to Earth was understood as the descent to Earth of the highest prince of the angels, who became man in Jesus Christ; he is to some extent identified with the angel prince Michael. In the old angel-Christology the concern is already expressed to preserve the oneness of God, the inviolable distinguishing mark of the Jewish and Christian faiths over against all paganism. The Son is not himself God, but as the highest of the created spiritual beings he is moved as close as possible to God. Arius joined this tradition with the same aim–i.e., defending the idea of the oneness of the Christian concept of God against all reproaches that Christianity introduces a new, more sublime form of polytheism.

This attempt to save the oneness of God led, however, to an awkward consequence. For Jesus Christ, as the divine Logos become human, moves thereby to the side of the creatures–i.e., to the side of the created world that needs redemption. How, then, should such a Christ, himself a part of the creation, be able to achieve the redemption of the world? On the whole, the Christian Church rejected, as an unhappy attack upon the reality of redemption, such a formal attempt at saving the oneness of God as was undertaken by Arius. The main speaker for church orthodoxy was Athanasius of Alexandria, for whom the point of departure was not a philosophical-speculative principle but rather the reality of redemption, the certainty of salvation. The redemption of humanity from sin and death is only then guaranteed if Christ is total God and total human being, if the complete essence of God penetrates human nature right into the deepest layer of its carnal corporeality. Only if God in the full meaning of divine essence became human in Jesus Christ is deification of man in terms of overcoming sin and death guaranteed as the resurrection of the flesh.

Augustine, of decisive importance for the Western development of the Trinitarian doctrine in theology and metaphysics, coupled the doctrine of the Trinity with anthropology. Proceeding from the idea that humans are created by God according to the divine image, he attempted to explain the mystery of the Trinity by uncovering traces of the Trinity in the human personality. He went from analysis of the Trinitarian structure of the simple act of cognition to ascertainment of the Trinitarian structure both of human self-consciousness and of the act of religious contemplation in which people recognize themselves as the image of God.

A second model of Trinitarian doctrine – suspected of heresy from the outset – which had effects not only in theology but also in the social metaphysics of the West as well, emanated from Joachim of Fiore. He understood the course of the history of salvation as the successive realization of the Father, the Son, and the Holy Spirit in three consecutive periods of salvation. This interpretation of the Trinity became effective as a “theology of revolution,” inasmuch as it was regarded as the theological justification of the endeavour to accelerate the arrival of the third state of the Holy Spirit through revolutionary initiative. The final dogmatic formulation of the Trinitarian doctrine in the so-called Athanasian Creed (c. 500), una substantia–tres personae (“one substance–three persons”), reached back to the formulation of Tertullian. In practical terms it meant a compromise in that it held fast to both basic ideas of Christian revelation–the oneness of God and divine self-revelation in the figures of the Father, the Son, and the Holy Spirit–without rationalizing the mystery itself. In the final analysis the point of view thereby remained definitive that the fundamental assumptions of the reality of salvation and redemption are to be retained and not sacrificed to the concern of a rational monotheism.

Characteristically, in all periods of the later history of Christendom in which a rationalistic philosophy was achieved and the history of salvation aspect of the Trinitarian question receded, anti-Trinitarian currents returned. Many, to some extent, consciously rejoined ties with Arius: the humanist Enlightenment of the 16th century and the so-called anti-Trinitarians of the Italian Renaissance. A direct connection exists between anti-Trinitarianism and 18th-century research into the life of Jesus. The oldest life of Jesus researchers in the 18th century, such as Hermann Reimarus and Karl Bahrdt, who portrayed Jesus as the agent of a secret enlightenment order that had set itself the goal of spreading the religion of reason in the world, were at the same time anti-Trinitarians and pioneers of the radical rationalistic criticism of dogma. The Kantian critique of the proofs of God contributed further to a devaluation of Trinitarian doctrine. In the philosophy of German Idealism, Hegel, in the framework of his attempt to raise Christian dogma into the sphere of the conceptual, took the Christian Trinitarian doctrine as the basis for his system of philosophy and, above all, for his interpretation of history as the absolute spirit’s becoming self-conscious. In more recent theology, at least in the accusations of some of its critics, the school of dialectical theology in Europe and the United States tended to reduce the doctrine of the Trinity and supplant it with a Mono-Christism.

In a brief but well-publicized episode in the mid-1960s in the United States, a number of celebrated Protestant theologians engaged in cultural criticism observed or announced “The Death Of God.” The theology of the death of God downplayed any notion of divine transcendence and invested its whole claim to be Christian in its accent on Jesus of Nazareth. Christian dogma was reinterpreted and reduced to norms of human sociality and freedom. Before long, however, the majority of theologians confronted this small school with the demands of classic Christian dogma, which insisted on confronting divine transcendence in any assertions about Jesus Christ.

The transcendence of God has been rediscovered by science and sociology; theology in the closing decades of the 20th century endeavoured to overcome the purely anthropological interpretation of religion and once more to discover anew its transcendent ground. Theology has consequently been confronted with the problem of Trinity in a new form, which, in view of the Christian experience of God as an experience of the presence of the Father, Son, and Holy Spirit, cannot be eliminated.

Hence like many Christians, Muslims also do not subscribe to the concept of  Trinity being against Monotheism (Tawhid). Allah says in Qur’an: “O Followers of the Gospel! Do not overstep the bounds (of the truth) in your religious beliefs, and don not say of God anything but the truth. The Christ Jesus, son of Mary, was but God’s Apostle- (the fulfillment of ) His promise which He had conveyed to Mary- and a soul created by Him. Believe, then in God and His apostles, and do not say,” (God) is a trinity”. Desist (from this assertion) for your own good. God is but one God; utterly remote is HE, in His glory, from having a son: unto him belongs all that is in the heavens and all that is on earth; and none is as worthy of trust as God” (Qur’an;4:171); “Well, they may have a little enjoyment in this world, but eventually they have to return to Us and then We will make them taste the severest punishment for their unbelief.”(Qur’an;10:70). The idea of vicarious sacrifice is therefore alien to Islam, and the claim that Jesus, or anyone else, had to be slain in atonement of human sins is refuted. God’s forgiveness, in Islam, is to be sought through sincere repentance and doing righteousness, without need for bloodshed. Salvation is granted by the grace of God. ).  To obtain salvation, a person must combine faith and action, belief and practice according to Qur’an: “As to those who believe and work righteousness verily We shall not suffer to perish the reward of any who do a (single) righteous deed.(Qur’an;18:30). “Then those whose balance (of good deeds) is heavy they will attain salvation” (Qur’an;23:102).

Related:

Islam & Christianity

Abrahamic Faiths-Commonalities

Misconceptions – Islam, Christianity & Judaism