Just look at the church! Who’s right? The Protestants, the Roman Catholics, the Greek Orthodox, the Mormons, the Messianic Jews? Even so-called Christians can’t agree among themselves.

I’m a little surprised at your objection, since there are several major variations in Judaism, ranging from Reconstructionist to ultra-Orthodox, and some branches don’t even regard the others as truly Jewish at all. So how can you indict Christianity because of differences? Still, I’m happy to answer your question: First, not everyone who calls himself a Christian really is.

Second, there is harmony around the world among true Christians regarding the fundamentals of the faith. Third, major disagreements tend to arise only when the authority of the New Testament is either denied or subjugated to human traditions and interpretations. When you get back to what Jesus and his followers taught, you can see who his real followers are today.

In the early 1980s, a Conservative rabbi invited me to have a public dialog/debate with him in his synagogue regarding Messianic prophecy, belief in Jesus as Messiah, and early Christianity (i.e., in the days of the New Testament, although the term Christianity did not exist at that time). This rabbi and I had been friends for some years, and we had both learned a lot from each other, so it was no surprise to me when this rabbi said during one of our exchanges, “One thing I’ve learned from Michael is that not everyone who claims to be a Christian is really a Christian. It’s really only a small percentage of those who are born into the Christian faith who are genuine believers.” Exactly!

You see, from the outside, it’s easy to think there are endless varieties of the Christian or Messianic Jewish faith to the point that it’s almost impossible even to define what makes someone a true Christian. But that is only a perception from the outside. From the inside, it’s all very clear. In fact, Jesus himself warned his followers that false messiahs and false prophets would arise and deceive many, and several decades later, his followers warned other Messianic believers—both Jewish and Gentile—about deceivers who would lead God’s people astray.

These warnings—with clear guidelines—are recorded in the New Testament itself, which means that the New Testament itself tells us how to distinguish between false believers and true believers.

“But,” you ask, “what about Christians who no longer accept the New Testament as divinely inspired? Surely you are aware that many Christian theologians don’t believe what Paul and Peter wrote or what Matthew and Luke claim Jesus said.”

Of course I’m aware of this. The problem is that these theologians are not Christians. If they deny the fundamentals of the faith—and again, I emphasize to you, there are clear fundamentals outlined in the Scriptures—then they have departed from the faith. In the same way, Orthodox Jews would say that Reform or Reconstructionist Jews who say that the Hebrew Scriptures were not divinely inspired and authoritative have deviated from the faith. The difference in this case is that no one is born a Christian (see above, 1.2) whereas people are born Jews.

Therefore, in the case of someone who claims to be a Christian and rejects the historic Christian faith, that person is not a Christian. In the case of a Jew who denies the God of Israel and the Torah of Israel, that person would still be a Jew, albeit a God-denying, Scripture-rejecting Jew. Both of these people, however, would be guilty of departing from the faith.

Interestingly, many Jewish scholars today recognize that in the time of Yeshua there were actually several Judaisms—as opposed to one Judaism—and these Judaisms each had some claim to being a legitimate expression of the faith. ²⁸³ The thing that made them Judaisms was that there were several core principles that united them, including belief in one God, belief in the special calling of the Jewish people, and belief in the Torah of Moses.

(By the way, one of the first-century Judaisms that had these core beliefs was Messianic Judaism! ²⁸⁴ It continues to have these beliefs to this very day.) The variations had to do with such things as belief in the authority of the traditions of the sages or belief in the afterlife, to name just a few. But their core beliefs were the same.

On the other hand, even within one particular Jewish expression such as Pharisaical (or Rabbinic) Judaism, there were constant arguments about minor details and legal rulings. In fact, one entire tractate of the Mishnah is devoted to disputed matters between the two leading Rabbinic schools. ²⁸⁵ How then did traditional Jewish scholars view these differences in their own traditions?

According to Maimonides, they were like the tips of the branches of a tree. The tree and the branches were all united, and it was only the tips—in other words, the smallest minutiae of legal interpretation—that showed any divergences. ²⁸⁶

With regard, then, to Jewish expressions of faith, there were major variations of Judaism in the first century of this era just as there are major variations in Judaism today, although some of today’s versions have really departed from any claim to the name Judaism, since they deny some of the core principles of the Jewish faith. It is also true that even within one particular stream of Judaism, there have been differences and there remain minor, peripheral differences.

The same summary can be given regarding the Christian, or Messianic Jewish, faith: There are different expressions of the Messianic faith that agree on the fundamentals, there are expressions of the faith that are not worthy of the name (since they have denied the fundamentals), and even within one particular stream of the faith, there remain minor, peripheral differences. What is important to remember is that the first believers in Jesus—for centuries, in fact—held to one primary body of authoritative writings, and therefore, we can identify with certainty today those who remain loyal to those writings, in spite of some minor differences and variations. ²⁸⁷

What then are the core beliefs of the Messianic (Christian) faith? Followers of Jesus believe that he is the Messiah of the Jewish people and the Savior of all humankind, that he came in fulfillment of the Hebrew Scriptures, that he shares both a human and divine nature (see vol. 2, 3.1–3.4 for detailed discussion of this), that he lived a sinless life, that he died for our sins and rose from the dead, that he will one day return and judge the world, that his sacrifice on our behalf is the only acceptable means of forgiveness, that through faith in him all people—even the worst of sinners—can be reconciled to God and begin a brand-new life, that true believers will be known by their good fruit, and that there will be a final heaven for believers and a final hell for those who refuse to believe. Those are just some of the core doctrines of the Messianic faith.

What I find amazing is that around the world, in every country I have visited, I have met Christians who experienced the same transforming power through faith in Jesus the Messiah, including former Hindus, Muslims, Buddhists, animists, atheists, terrorists, alcoholics, drug addicts, prostitutes—you name it—and who believe in the same fundamentals of the faith.

Friends of mine who have spoken in as many as ninety different countries can attest to the same phenomenon: There is a supernatural unity among those who truly believe and who have come to know God through Yeshua. It’s wonderful! This supernatural unity of the church is actually one of the best arguments for the Messianic faith, as opposed to being its Achilles’ heel.

²⁸³ This was expressed in the title of the important study cited above (n. 61), edited by Neusner, Green, and Frerichs, Judaisms and Their Messiahs, and is commonly accepted by the great majority of Jewish and Christian scholars. As stated simply by B. Pixner (in Charlesworth and Johns, Hillel and Jesus, 193), “The Judaism of the Second Temple period, and in particular the Judaism at the time of Jesus and the primitive church, was not monolithic in its religious attitude, but rather pluralistic.” One of the conclusions reached by the contributors to this volume was that, “Both Hillel and Jesus set in motion perspectives, commitments, and means of adhering to and inculcating traditions that founded respectively Rabbinic Judaism and Christianity” (460–61).

²⁸⁴ As noted in 1.5, n. 10, Gabrielle Boccaccini has recently argued that Christianity be recognized as a Judaism (see his Middle Judaism, with some strictures in the foreword by J. H. Charlesworth, xviii), citing the judgment of scholars who underscore the Jewishness of early Christianity (see esp. 13–18); cf. also the challenge of Geza Vermes, Jesus and the World of Judaism (Philadelphia: Fortress, 1983), 87–88, for a new “Schürer-type religious history of the Jews from the Maccabees to a.d. 500 that fully incorporates the New Testament data.” See also Marvin R. Wilson, Our Father Abraham: Jewish Roots of the Christian Faith (Grand Rapids: Eerdmans, 1989).

²⁸⁵ It is called Eduyot (meaning, “Testimonies”). According to Rabbi Adin Steinsaltz, The Essential Talmud (New York: Bantam, 1976), 91, Eduyot is a “compilation of testimonies on ancient halakhah that was in danger of falling into oblivion and on unusual aspects of halakhah, apparently amassed at a special session of the Yavneh court.” See also H. L. Strack and G. L. Stemberger, Introduction to the Talmud and Midrash, trans. Markus Bockmuehl (Edinburgh: T & T Clark, 1991), 129.

²⁸⁶ Cf. Maimonides’s introduction to his commentary on the Mishnah for a detailed defense of the essential unity and harmony of the Rabbinic traditions.

²⁸⁷ So, for example, despite their claims to the contrary, Mormons are in no sense of the word Christian, since they base their beliefs more on the Book of Mormon than on the Bible and they deny certain fundamental tenets of Christianity. See James R. White, Is the Mormon My Brother? Discerning the Differences between Mormonism and Christianity (Minneapolis: Bethany, 1997).

Brown, M. L. (2000). Answering Jewish objections to Jesus, Volume 1: General and historical objections. (205). Grand Rapids, Mich.: Baker Books.

Just look at the church! Who’s right? The Protestants, the Roman Catholics, the Greek Orthodox, the Mormons, the Messianic Jews? Even so-called Christians can’t agree among themselves.