1. Islam teaches salvation through works and self-righteousness.
In this regard, Islam is no different than any other false religious system, including Mormonism, Jehovah's Witnesses, Budhhism, and Orthodox Judaism, to name a few. Islam has in common with these that mankind ultimately plays a central role in his eternal destination, and that if he does enough good deeds and lives a good life he will ultimately be rewarded in the afterlife. Christianity is unique among world religions because the Bible tells us that we can do nothing to earn or deserve our salvation, but that our salvation comes through faith in Jesus Christ and his blood atonement sacrifice for our sins.
Islam teaches that two recording angels follow each of us and they keep a tally of our good and bad deeds. On judgemen day the good and bad deeds will be placed on opposite sides of a scale and we hope to have enough good deeds to offset the bad ones. Muslims live and die by the scales. Problem: a Muslim will never know completely if he/she has enough good deeds on account; assurance of salvation cannot be known until judgment day.
Sura 21:47 - We shall set up scales of justice for the Day of Judgment, so that not a soul will be dealt with unjustly in the least
Sura 23:103 - Then those whose scales are heavy, they are the successful. But those whose balance is light, will be those who have lost their souls, in Hell will they abide.
Sura 101:6-9 - Then, as for him whose scales are heavy (with good works), Will be in a life of good pleasure and satisfaction. But he whose balance (of good deeds) will be (found) light, Will have his home in a (bottomless) Pit.
2. Islam is more than just a religion; it is a complete way of life.
Many in the West think of Islam as just another religious viewpoint among other major world religions. But to a Muslim, Islam is more than just a religion. Islam is not just a method of fulfilling religious obligations: praying, giving, fasting, pilgrimmage. Islam encompasses these and much more. To a Muslim, the goal of this life is to emulate the prophet of Islam, Muhammad, in every respect.
The behavoir or actions of Muhammad is known as the "sunna" or the example of the prophet. Islamic law - Shari'a - dictates how a Muslim is required to respond not just in religious rituals, but in every area of life. If Muhammad did something a certain way, a Muslim must also do it the same way. The rules of Shari'a law dictate every facet of life: family, business transactions, marriage, divorce, inheritance, bathing and cleansing, goooming, dressing, money. If Muhammad brushed his teeth a certain way using a certain kind of toothbrush, a Muslim must brush his teeth the same way. If Muhammad cleansed himself a certain way, Muslims do the same. This is how a Muslim gains the good deeds that he hopes will tilt the scales in his favor on judgement day.
The Sunnah of the Prophet Muhammad is therefore, next to Qur'an, the second source of Islamic law and of social and personal behavior. In fact we must regard the Sunnah as the only valid explanation of the Qur'anic teachings and the only means to avoid dissensions concernin their interpretation and adaptation to personal use ... So long as we believe that this Book is the Word of Allah perfect in form and purpose, the only logical conclusion is that it never was intended to be used independently of the personal guidance of the Prophet which is embodied in the sysem of the Sunnah. (Muhammad Assad, Islam at the Crossroads, p. 117 118; quoted in Sunan Nasa'i)
3. Islam does not mean "peace."
Muslim apologists and pro-Islamic organizations like CAIR (The Council for American-Islamic Relations) try to deflect the negative stereotypes of violent Muslims by asserting that the word Islam means "peace." In reality, Islam means "to submit" and a Muslim is one who submits.
In order to find the meaning of a certain word in the Arabic dictionary, it is essential to search for the three letter infinitive verb which is called the root. Many words can be derived from the same root, but they don't necessarily have to have any similarity in their meaning. The word Islam, which means "submission", is derived from the infinitive Salama. So is the word Salam which means "peace" and so is the verb Salima which means "to be saved or to escape from danger." One of the derivations of the infinitive Salama means "the stinging of a snake" or "The tanning of the leather." Hence, if the word Islam has something to do with the word Salam i.e. "Peace", does that also mean that it must be related to the "stinging of the snake" or "tanning the leather?"
Muhammad used to send letters to the kings and leaders of the surrounding countries and tribes, inviting them to surrender to his authority and to believe in him as the messenger of Allah. He always ended his letters with the following two words: "Aslim, Taslam!". Although these two words are derived from the same infinitive Salama which is the root of Salam, i.e. "Peace", neither one of them implies the meaning of "peace". The sentence means "surrender and you will be safe", or in other words, "surrender or face death". So where is the meaning of "Peace" in such a religion that threatens to kill other people if they don't submit to it? (Source)
4. The Goal of Islam: All people become Muslims
Islam is a missionary religion just as is Christianity. As such, one of the primary goals of Islam is for all people everywhere to embrace Islam, acknowledge Allah as the only one and true God, and acknowledge Muhammad as the final prophet of God. One difference between the two religions is how this missionary activity is carried out.
Christainity has always been propogated by the truth claims of the Bible itself, attested to by signs and wonders (miracles), and witnessed in new believers by a regenerated spirit. Jesus never advocated violence against others. The truth of the gospel message needs no help; it stands on its own.
Islam is propogated by dawah and jihad. Dawah means to give an invitation to accept Islam and embrace Allah and Muhammad. Jihad is used to enforce that belief and the acceptance of Islam through violence if necessary. The concept of jihad has enormous support in both the Qur'an and hadith, as well as all four schools of Islamic law. Only in the west is jihad whitewashed as an inner spiritual struggle against the evil desire of oneself. In Muslim nations, jihad clearly is understood as the Qur'an and hadith teach, and as Muhammad himself set the example.
In his book, "Jurisprudence in Muhammad's Biography", the Azhar scholar, Dr. Muhammad Sa'id Ramadan al-Buti says the following (page 134, 7th edition):
"The Holy War, as it is known in Islamic Jurisprudence, is basically an offensive war. This is the duty of Muslims in every age when the needed military power becomes available to them. This is the phase in which the meaning of Holy War has taken its final form. Thus the apostle of God said: "I was commanded to fight the people until they believe in God and his message ..." (Source)
Ibn Ishaq, Muhammad's earliest and most authoritative biographer, sums up Muhammad's life and example:
God sent Muhammad with this religion and he strove for it until men accepted it voluntarily or by force. Once they had entered it they were God's proteges and neighbors under His protection. (The Life of Muhammad: Sirat Rasul Allah, ibn Ishaq, translated by A. Guillaume, Oxford Press, page 669).
While Christianity has spread generally due to the truth claims of the Bible, the power of the Holy Spirit in the lives of believers, and the powerful testimonies of lives that have been changed, Islam needs to spread by force. Why would anyone follow a religion that must be forced upon others because it cannot stand on its own merits?
5. Islam is not the fastest growing religion.
In terms of conversion rates, Islam is not growing very rapidly. The majority of growth in Islam can be attributed to large reproduction rates among Muslim families. The reality is that many more people are turning from Islam to Christianity than the other way around. This is especially true in predominately Muslim nations where Christianity is outlawed, such as Iran. Jesus is appearing to Muslims through dreams, visions, and is speaking to Muslims through copies of the Bible that find their way into these nations.
For a small sample of conversion testimonies, check out the following links:
Praise God! Just as in the early days of the church, the message of eternal salvation available through the blood of Jesus Christ is being heard where it is most needed. "For the word of God is living and powerful, and sharper than any two-edged sword, piercing even to the division of soul and spirit, and of joints and marrow, and is a discerner of the thoughts and intents of the heart." (Hebrews 4:12)