Since both Islam and Christianity have their roots in Abrahamic religion, the argument is often made that this common root of Abraham makes them similar. Muslims make this argument mostly in the West when they want to be ecumenical and where they find themselves a minority religion. Muslims even want to be accepted as the third foundational religion in the United States along with Judaism and Christianity precisely because of these roots.

Nothing could be further from the truth. The basic values and principles of United States documents come from the Bible not from the Quran. The differences between the two faiths are so profound that merely coming from the same root does not in any way make them similar. In short, in all the basics of their respective faiths, the gulf is so vast that we can say that they are radically different; and being radically different, they have almost nothing in common.

I should like to compare these two religions without trying to make one better or worse than the other. That will be up to the individual to choose and decide. What we can do is to show the radical differences between the two faiths and let everyone choose for himself. Consider the following:

1. In Christianity, God is love essentially through and through. He is not merely loving; His very nature is love. Forgiveness, compassion, mercy belong to His very nature, and He must exercise these virtues accordingly because they come from His nature. In Islam, God is beyond all categories so that we can know nothing of God's nature. He can be merciful and forgiving only if he chooses to be so.

2. In Christianity, God loves all men and desires their salvation and leads them to the truth. God rejects no one and seeks out ways by His grace to save all men and to be with them. In Islam, God loves only Muslims and rejects and hates infidels who have rejected Islam. All men must be converted to Islam or they are going to hell.

3. In Christianity, God beckons all men to come to Him freely and never uses force or coercion. Salvation is offered to all men and women, but they must freely choose to accept that salvation. In Islam, force may be used to convert men to Islam. That is the very meaning of jihad which has been part of Islam from its beginning fourteen hundred years ago. If they reject Islam, it is because of bad faith and they will go to hell. This is what one Muslim scholar says of violent jihad: ''Jihad is in defense of and for the spread of Islam . . . it is jihad for the sake of Allah. Moreover, there are religious scholars who view it as the Sixth Pillar of Islam'' (Sheik Wajdi Hawaet al Ghazwi, in a sermon at Mecca, Oct. 6, 2001).

4. In Christianity, God calls us freely and he must have our ''yes'' even for our own salvation. There is no predestination or force in Christianity. God gives freely but men must respond freely. Man remains free to accept or reject God's call. Islam is a determinist religion. Everything is by the will of God which cannot be resisted and will necessarily come about no matter what we do.

5. In Christianity, man is endowed and created by God with human rights so that every man and woman are equal in this sense. All men and women have human rights which must be respected by everyone and by the state. In Islam, human rights belong properly only to Muslims because they are better than all other peoples. Other men and women do not have rights which Muslims must respect.

All Blasphemous

6. In Christianity, God is love; therefore He is Father. We are destined to be one with Him in eternity, and salvation lies in union by love with God by His holy grace. There is an intimate relationship between men and God to the point where men participate in the divine nature. Eternal life is spiritual in nature, and union with God is brought about by love. In Islam, all these terms of intimacy and union with God as Father and participating in the divine nature are blasphemous. We cannot come close to God, and our heavenly rewards remain (in eternal life) terrestrial in nature: things which we have in this life but magnified many times over: fine foods, wine, beautiful women.

7. In Christianity, there is a serious effort to be ecumenical, to understand other religions, and to accept the fact that other religions have elements of truth. Islam claims that it alone has the fullness of truth and that all other religions are lies, deceptions and works of the devil. Islam teaches that because it has the fullness of truth, other religions cannot possibly have elements of truth. Outside of Islam, there is only untruth and eternal damnation. Everyone must accept Islam or go to hell.

8. In Christianity, God is one God in three persons: Father, Son and Holy Spirit, i.e., the Trinity. ''The mystery of the Trinity in itself is inaccessible to the human mind and is the object of faith only because it was revealed by Jesus Christ, the divine Son of the eternal Father'' (Catechism of the Catholic Church). In Islam, all talk of Trinity is blasphemy because God is absolutely and eternally one. It calls the Trinity polytheism and those who believe in it polytheists. God is one, absolute, almighty and unknowable. We may only worship God, never be united with him. God is merciful but only if he wants to be.

9. Christianity mandates love of all men and women, even of enemies. We must love even enemies and endeavor to help them in any way we can. Love must characterize every action of the Christian. We must love sinners and forgive them their sins if they repent sincerely. Seven times seventy. We may never hate anyone or desire vengeance. In Islam, we must love only our fellow Muslims and hate all the rest. We must particularly hate Jews and seek to kill them, as well as all infidels, any chance we get. Hate of enemies is even mandated in the Quran and by its preachers all over the Muslim world.

10. The Christian must never lie under any circumstances. The lie is always forbidden even if our lives depend on it. In Islam, Muslims may lie to protect and promote Islam, as well as to save oneself from persecution and death. The lie is an instrument of religious propaganda.

11. Every Christian is free to leave the church, the faith, the practice of that faith. No force or coercion must ever be used to keep one in the faith just as God will not use force on anyone to enter the faith. In Islam, no one may leave the faith under penalty of death. If a Muslim joins another faith or church, he may be put to death by any of the faithful. One is not free to leave Islam. It would be to turn one's back on truth.

12. Christians may defend themselves only when they are unjustly attacked or invaded. This is known as the just war theory. The Christian may fight or use violence only in a defensive war, never an aggressive one. Capital punishment is becoming obsolete. For the protection and promotion of Islam, any and every means may be used and whatever is at hand. This violent jihad is incumbent on every Muslim male for the protection and promotion of Islam, and it is contained in the Quran.

13. In Christianity, all women are equal to men in every respect before the law and must be respected as equals. They may never be beaten or discriminated against in any war. Christianity is strictly monogamous. Divorce laws are open to women if that is their desire. In Islam, women may be beaten under certain circumstances, are not the equals of men in many respects of religious law. Muslim men can practice polygamy, with up to four wives allowed, and only men can divorce a spouse.

Sharia Law

14. Christianity knows no specific religious law under which they must live in all things outside of the community. Democracy, socialism, free enterprise, capitalism are all compatible with this faith. In Islam, all Muslims must endeavor not to live under secular law but must live under Muslim sacred law (sharia) and Muslim leaders. In Muslim countries, this religious law controls all aspects of life, private and public.

15. In Christianity, there is a clear division between church and state with each acting in its own independent sphere. Some conflict sometimes comes about, but generally one does not intrude into the jurisdiction of the other. Christianity has no political agenda, and Christians are free to elect the government they desire. The people are the final arbiter in a democracy: ''We the people in order to form a more perfect union. . . .'' In Islam, there is always union of church and state, and it has a clear political agenda which is to convert the whole world to Islam. Muslims must live under sacred law (sharia) and there can be no separation of mosque/state because God rules in heaven as on earth. Democracy and ultimate rule by the people is incompatible with Islam except as a practical matter, and only divine law is applicable to all things, public as well as private.

16. In Christianity, all men and women are equal before the law, with no discrimination before an impartial judiciary applying secular law only. No religion or religious law can ever tell the state what to do or not to do. That is the prerogative of the people. The First Amendment even protects all those who desire to criticize a particular religion. In Islam, infidels and women are not equal before the law. Adulterers and homosexuals must be stoned to death; thieves must have their limbs removed for theft, every criticism of Islam or Mohammad is punishable by imprisonment or death; women are to receive less in inheritance, and their testimony is worth less than that of a man.

17. In Christianity, religious freedom is respected and embraced. Neither the state nor any religious group may use violence or coercion to convert others to the faith unwillingly. This is guaranteed under the First Amendment to the Constitution. Government must be neutral in its attitude toward all religions. In Islam, there is hardly any religious freedom in any Muslim country. Since Islam has total truth, how can there be religious freedom? Islam divides the world into the lands of Islam and the lands of war where violent jihad may be used to make those lands Muslim. No Muslim country has any law or constitution guaranteeing religious freedom to everyone. In fact, the Quran forbids it. Religious freedom is incompatible with Islam.

18. Christians may travel everywhere unimpeded by law or government. Non- believers may enter Christian churches, even the most sacred ones, and are encouraged to do so. In Saudi Arabia, no other religion but Islam is even permitted and only Muslims may enter the sacred cities of Mecca and Medina. Any unbeliever caught there is subject to the penalty of death. Few churches are permitted in Muslim lands, while mosques are freely built everywhere in the West.

'Cover Up'

19. In Christianity, men and women are equal. They may worship together as a family, they may attend church together, and women are not bound to dress in any particular way. In Islam, Muslims strictly separate all men and women everywhere: in schools, in mosques, etc. They may not pray together as a family unit but are separated in mosques. Women are required to ''cover up.''

20. In Christianity, in the holy books of the New Testament and the teachings of Jesus, there is not one word of hatred or death for those who do not share the faith. On the contrary, Christians must love one another and enemies as well. In Islam, the Quran is full of violence, hatred of Christians and Jews and the killing of unbelievers. The one who converts from Islam to another faith is to be put to death.

21. In Christianity, men and women are both created in the image and likeness of God, i.e., the more they love, the more they become like God. In Islam, men and women are only created to worship and obey God under the sacred law revealed by Mohammed called sharia which rules every aspect of life, both private and public. There is no likeness of God in man.

22. In Christianity, freedom characterizes the Christian message. While Christians have failed in this respect in the past (Crusades, Inquisitions, witch trials, persecution, religious wars), they have apologized for this and have determined in their sacred documents never to resort to force again. Christians are free to accept or reject Christianity without any disability. In Islam, there is only one freedom and that is to accept God's law and follow it. After that there is no freedom. Even the ''freedom'' to leave Islam for another religion is punishable by death.

23. In Christianity, eternity, while intellectually obscure (''we see through a glass darkly''), remains in the form of union, a relationship of love, because that is who God is. Eternal life and rewards in Islam are terrestrial in nature, only multiplied: wine, beautiful women, fine foods, etc.

24. In Christianity, the practice of abortion, embryonic stem cell research, euthanasia, clitorectomy are all forbidden. In Islam, abortion, embryonic stem cell research, euthanasia are also forbidden. But many Muslims practice clitorectomy on their young girls to make sure they are virgins at marriage. Women have no freedom to marry whom they wish. Muslim men may marry infidels, but Muslim women cannot.

All these contrasts show the radical differences between Islam and Christi- anity. As I said, each congregant must choose which religion to follow and, at least in the West, each is free to follow the chosen religion in freedom and liberty.

If there is one overriding characteristic in the two faiths, it is freedom or lack thereof. That is what makes the West so superior to the Muslim world: the freedom to choose. Only in the West may one choose freely which religion he or she will follow. That simply is not true in the Muslim world. TP

Mr. Riga, an attorney and author, writes from Houston, Texas.