Marshall Taylor, PhD discusses the insufficiency of Islam with an insightful analogy:
The Analogy of the Bow and Arrow
Muslims are also said to “adore the one true God.” Thomas Aquinas would agree with this by adding a clarification.
One can “adore” in two ways.
First, one can adore rightly be adoring the right object (Trinity) and adoring in the right manner (approved liturgy, sacraments, approved prayers and forumalas). This would be the adoration that Catholics offer to the glory of God.
Secondly, one can direct adoration in the right direction but not understand the target. For example, if you shot an arrow down range but your had poor eyesight and could not see the target, then you might shoot in the right direction without seeing the destination. You shot the arrow at the proper target but you don’t see, know, perceive, or understand the target. Moreover, in this case, the bow would be too weak to get the arrow to the destination. The arrow would fall short.
This “blind archer with a weak bow” is Islam. They shoot their arrow in the right direction (toward the “God of Abraham”), but they do not understand the target and their bow is too weak because their bow lacks the power of grace.
So the Muslim “adores the one true God,” just as a blind archer “shoots at the one true target.”
Yet the Catholic “adores the one true God,” as well-practiced archer who can see the target and has a powerful 70 pound bow stringed with grace! Through Christ, our adoration is carried to heart of God.
Why Muslim adoration is insufficient
Through Christ, our adoration is made perfect and well-pleasing because Christ is the perfect and divine High Priest by virtue of hypostatic union that unites His divinity to His assumed humanity.
Mohamed’s Quran explicitly denies this truth:
They do blaspheme who say: “God is Christ the son of Mary.” They do blaspheme who say: God is one of three in a Trinity: for there is no God except one God Allah. If they do not desist from their word of blasphemy, verily a grievous penalty will befall the blasphemers among them. Christ the son of Mary was no more than a Messenger; many were the Messengers that passed away before him.” Quran, Sura 5:72-73, 5:75
So Muslims should be recognized as “further along the path” than other non-Christians, but their rejection of the Trinity and their rejection of Christ as the Son of God means that their “arrow of adoration” cannot reach the intended target.
This is why Christians must be charitable witness of the Son of God, and we must continue to fund and send missionaries into Muslim nations. They profess to have the faith of Abraham, but they do not possess the fullness of God’s message for humanity.
Muslim Worship in the Catechism
By Dr. Taylor Marshall