Yes, Christians and Muslims worship the same God, according to the teaching of the Magisterium:
Catechism of the Catholic Church: “The Church’s relationship with the Muslims. ‘The plan of salvation also includes those who acknowledge the Creator, in the first place amongst whom are the Muslims; these profess to hold the faith of Abraham, and together with us they adore the one, merciful God, mankind’s judge on the last day.’ ” [CCC 841; inner quote from Vatican II, Lumen Gentium 16]
Second Vatican Council: “The Church regards with esteem also the Moslems. They adore the one God, living and subsisting in Himself; merciful and all- powerful, the Creator of heaven and earth, who has spoken to men; they take pains to submit wholeheartedly to even His inscrutable decrees, just as Abraham, with whom the faith of Islam takes pleasure in linking itself, submitted to God. Though they do not acknowledge Jesus as God, they revere Him as a prophet. They also honor Mary, His virgin Mother; at times they even call on her with devotion. In addition, they await the day of judgment when God will render their deserts to all those who have been raised up from the dead. Finally, they value the moral life and worship God especially through prayer, almsgiving and fasting.
“Since in the course of centuries not a few quarrels and hostilities have arisen between Christians and Moslems, this sacred synod urges all to forget the past and to work sincerely for mutual understanding and to preserve as well as to promote together for the benefit of all mankind social justice and moral welfare, as well as peace and freedom.” [Vatican II, Nostra Aetate 3]
The above magisterial teachings assert that Muslims “adore”, that is to say, worship, “the one merciful God” and they do so “together with us”. Therefore, Christians and Muslims worship the very same God. And this is true because the faith of Islam includes substantial and essential truths about God: that He is one, merciful, all-powerful, has spoken to us, has created heaven and earth, requires us to live a moral life, and will judge us on the last day. And the same can be said about the Jews. Therefore, Christians, Jews, and Muslims worship the same God.
And that is why the recent Popes have referred to these three religions as “the three great monotheistic religions”.
Pope Benedict XVI: “Jerusalem is the cross-roads of the three great monotheistic religions, and its very name ‘City of Peace’ expresses God’s plan for humanity: to make it one great family. This design, announced to Abraham, was completely fulfilled in Jesus Christ, whom St Paul calls ‘our peace’, because through his Sacrifice he forcefully broke down the dividing wall of hostility (cf. Eph 2: 14). Thus all believers must leave behind them their prejudices and desire to dominate and must in harmony obey the fundamental Commandment: in other words to love God with all one’s might and to love one’s neighbour as oneself. It is to this that Jews, Christians and Muslims are called to bear witness, in order to honour with acts that God to whom they pray with their lips.” (General Audience on his pilgrimage to the Holy Land, 2009)
Pope Benedict uses the phrase “the three great monotheistic religions”. But he could not use that expression if only one or two of the three religions worshiped the one true God. He also explains that Jews, Christians, and Muslims honor and pray to God, implying that we pray to the same God. There are differences between these three religions, which divide us. But the similarity is that we worship one and the same God.
Pope Saint John Paul II: “Praise to you, followers of Islam in Azerbaijan, for being open to hospitality, a cherished value of your religion and your people, and for having accepted the believers of other religions as brothers and sisters.
“Praise to you, Jewish people, who, with courage and constancy, have kept your ancient traditions of good neighborliness, enriching this land with a contribution of great value and depth.
“Praise to you, Christians, who have given so much, especially through the ancient Church of the Albans, in shaping the identity of this land. Praise especially to you, Orthodox Church, witness to God’s friendship with man and a hymn extolling his beauty. When the fury of atheism was unleashed in this region, you welcomed the children of the Catholic Church who had lost their places of worship and their pastors, and put them into contact with Christ through the grace of the holy Sacraments.
“Praised be God for this testimony of love, borne by the three great religions!” (Address, May 2002)
Pope Saint John Paul II calls Christianity and Judaism and Islam “great religions”. Each is great in its own way. Now this does not imply an absolute equality, as if the differences between the three were of no importance. As Catholic Christians, we believe that Christianity is the truest form of religion, and Catholicism is the truest form of Christianity. Even so, Judaism is the foundation on which Christianity is built. Judaism is a true religion established by God, before Christianity began. And the hundreds of millions of faithful Muslims, who worship God in the Islamic faith, who love God and neighbor, bear witness to the truth of their religion. For every religion that teaches the love of God above all else, and the love of neighbor as self is a true religion.
Some commentators claim that Christians do not worship the same God as Muslims, due to the differences in our beliefs about God. But if it were true that some incorrect beliefs about God entirely invalidated worship, so that the believer was not worshipping the one true God at all, then none of us would qualify as worshippers of God.
The vast majority of Catholics hold incorrect ideas about God. They do not understand that God is entirely unchanging. They do not understand the eternity of God. They do not understand that the Three Persons of the Trinity are consubstantial. They do not understand that the oneness of God implies that His existence is His acts. They do not understand that in God, mercy and justice and love and knowledge and existence are exactly the same. They do not correctly understand the hypostatic union, nor transubstantiation, nor salvation theology. They badly misunderstand the grace of God. And when we consider the Protestant understanding of God, there are even more errors.
If the Muslims and Jews do not worship the same God, because they misunderstand certain truths about Him, then neither do Protestants or the vast majority of Catholics worship the one true God — according to that foolish standard.
Instead, it is sufficient for a believer to understand that God is eternal, all-powerful, all-knowing, loving, merciful, and holy; that He requires of us both worship and a moral life; that He offers to us eternal salvation in Heaven. It is sufficient for any religion to worship the one true God, if that religion teaches the love of God above all else, and the love of neighbor as self. For the core truth of any true religion is the love of God and neighbor.
When at last the faithful, who die in a state of grace, receive the Beatific Vision of God in heaven, they will all know God with such clarity and fullness (as much as our finite natures, assisted by great graces, allows) that our former knowledge will seem like straw by comparison.
On the feast of St. Nicholas [in 1273, Aquinas] was celebrating Mass when he received a revelation that so affected him that he wrote and dictated no more, leaving his great work the Summa Theologica unfinished. To Brother Reginald’s expostulations he replied, “The end of my labors has come. All that I have written appears to be as so much straw after the things that have been revealed to me.” When later asked by Reginald to return to writing, Aquinas said, “I can write no more. I have seen things that make my writings like straw.” [Catholic.com]
How arrogant and ignorant it is for Catholics to claim that Muslims or Jews do not worship the same God, because Catholics have the better understanding. Our understanding, in so far as it is correct, is nevertheless like straw compared to our future knowledge in the Beatific Vision. And even then, we shall never fully comprehend the infinite Divine Nature.
I should also point out the certitude in faith that some Catholics and Protestants die unrepentant from actual mortal sin, and so they never receive eternal life in Heaven; they are condemned to eternal punishment in Hell. But it is just as certain that some Jews and some Muslims die in the state of grace, and will have eternal life in Heaven. How foolish is it to claim that Jews or Muslims do not worship the same God, when every day some Christians are dying and being condemned to Hell, despite the teachings of Christ.
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