It is a well known fact that many Muslims are very proficient at memorizing parts or the whole of the Koran (it is about the length of the New Testament). Christians often lack memorization skills (and many of them even neglect to study the Scriptures). One of the reasons is the great length of the Bible. It consists of two parts and the Old Testament comprises about 75% of the whole. Nowhere is it said that the Old Testament is old and worth less than the New Testament. It is true that there are many New Testament believers that neglect the Old Testament (to their own detriment), because the New Testament is intricately linked to the Old. So which parts of the Old or New Testaments should Christians memorize?
Regardless, let us discuss why Muslims memorize the revelations that Mohammad, the prophet, got from Allah. We can only understand it if we compare the Bible and the Koran. The Bible is a personal book that addresses each of its readers with the intent of getting the person involved in a personal relationship with Jesus (whom we meet in the Bible). Thus we find in Scripture that God (Jesus) speaks to us and instructs us individually with the help of the Holy Spirit. Without the Holy Spirit it is impossible to understand the Bible. That is why we should be wary of unbelievers' interpretations of the Bible. They do it to discredit the Bible, because they cannot interpret it correctly.
To memorize verses or books is wonderful, but in my own experience I found it very time consuming. The time could be better spent reading the Bible and reacting to God's advice and teachings. As each person's circumstances are different, we obviously need personalized instructions. That is why a Personal Trainer, the Holy Spirit, is so logical. Many people use personal trainers for physical exercise, why not for instruction in God's affairs? The Holy Spirit is not involved in the Koran, as it denies the Trinity (Father, Son and Holy Spirit). The Koran does not have anything like a personal trainer to guide the reader individually, as Islam is not about a relationship, but about the religion of conforming to Allah's wishes. Eventually the only things a Muslim can do is to memorize the Koran and to learn the Arabic language and recite the verses with the right pronunciation. Muslims claim that the original Arabic is absolutely pure and only in that language can the Koran come to its full potential: 'Muslims are right when they say it cannot really be reproduced in another language.'1 Contrary to that, Christians can spend their time listening to God's voice (in Scripture), studying and getting to know the Lord better (always guided by the Holy Spirit).
When Muslims debate Christians they recite Bible verses that they have memorized, one after the other. That is their tactic of intimidation. Ask yourself what people who believe in Allah have to do with the Bible? Evolutionists, atheists, occultists, humanists and other religions don't accept the Bible as the Word of God. What specifically is Islam's problem? God and Allah are different persons, the Bible and the Koran differ completely, and if they want to attack the Bible, they are welcome. They in any case have to 'contort' the Scriptures to prove what they want, and that is not worth very much. They are not the first people who deny the deity of Christ and His sacrificial death on the Cross, and they won't be the last. If they want to claim that the Koran is the last and final revelation of Allah it is fine, but what does that have to do with the Bible? The Bible stands alone as the sole revelation in history of the Creator God. If they want to argue which book is true, let them start by bringing a historical revelation of Allah in Arabia. Then the Bible and the Koran can be compared and discussed. Till then, don't be intimidated by their good memorization skills. That does not put the Koran on a higher level than the Bible, the living Word of the God of Abraham, Isaac and Jacob.
- J Gilchrist, The Qur'an, The Scripture of Islam, Life Challenge Africa, 1995, p ii.