What God must gentiles believe in?

Question

In the Rambam's Mishne Tora, the end of chapter 8 of M'lachim reads:

Any [gentile] who accepts seven commands and is careful to fulfill them is among the pious of the nations of the world and has a share in the world to come. But that's provided he accepts them and does them because God commanded them in the Torah and informed us through our leader Moshe that descendants of Noach had been commanded them. If, on the other hand, he does them because of the force of logic, he is… not one of the pious of the nations of the world, but one of their wise men.

Now, Jews must — again, I'll quote Mishne Tora, this time from Y'sode Hatora chapter 1:

know there is a first existing thing who brings all that exists into existence.…

And if one could conceive that all other things in existence, except him, would not exist, then he alone would exist: he would not be nonexistent due to their nonexistence, for all existing things require him but he does not require them or any one of them. Thus, his truth is not the truth of any one of them:… there is no truly existing thing besides him like him.…

And he guides the wheel with infinite strength, with unending strength….

And this god is… not one like a type that includes many individuals, and not one like a body that has many divisions and extents, but a oneness like no other.…

It's clear in the Torah and the books of the prophets that God is no body….

We seem to have a few aspects of God that Rambam holds necessary for Jews to believe (or know): that he exists, that he creates every other existence, that his existence is true whereas others' is dependent on his, that he guides all events, that he is indivisible, and that he is incorporeal.

Which of these beliefs, according to Rambam, are required of gentiles in order to be considered "among the pious of the nations of the world and [to have] a share in the world to come"?

Answer 1

The Chazon Ish (Y.D. 62:20) writes that in all likelihood, Noahides are commanded against heresy, because belief in God is the foundation for all 7 commandments that they are actually commanded in. However, he himself is unsure whether this heresy is defined in the same way as it would be for a Jew, considering that there are some authorities who permit Noahides to believe in other gods in addition to God.

R. Mayer Twersky published an article on the topic of what Noahides must believe in. The Rambam writes (Hil. Yesodei HaTorah 1:7) that, not only must one believe that God is One, eternal, and incorporeal, but that these three factors are dependent on one another. Thus, R. Twersky writes, just like the Jews must believe that the creator and source of all that exists is one, eternal, and incorporeal, so too a gentile who doesn't believe in this doesn't believe in God.

The Rambam doesn't specifically write that one must believe that God created the world from nothing, though this does appear in the corrected version of his 13 foundational beliefs listed in his introduction to Perek Cheilek. However, R. Yaakov Kamenetsky writes in several places (Emes L'Yaakov to Beraishis 8:22, Shemos 20:10) that although non-Jews do need to believe in God, they are not obligated to believe that God created the world, merely that He is the cause of the world's existence.

Rav Twersky, however, goes a step further than requiring Noahides to believe in the same God as the Jewish people: in the aforementioned article, he writes that according to the Rambam, a Noahide needs to believe in the divinity of the Torah as well as all other 13 principles in order to be given a share in the afterlife. He proves this from the fact that, in his listing of the beliefs that would cause one to be barred from the world to come, (Hil. Teshuvah 3:5-8), he writes that Christians and 'Hagarites' (Muslims, I believe) are heretics, because they believe that the Torah has been superseded by another book or prophecy.

Answer 2

First it should be noted that the 7 Noahide laws themselves do not say anything about necessitating a belief in God. As summarized by this article on Simple to Remember The relevant law is #4, namely it is forbidden to worship idols.

However the whole area of relations between humanity and its Creator has been placed under specific requirements, namely that only His truth and unity should be the subject of belief, worship and philosophy.

As you already explained, Rambam says that a belief in a single God, and a belief that this God commended the 7 Noahide laws, are a prerequisite, but he doesn't clearly say how detailed or accurate their understanding of God must be besides that.

There is a good book on the topic, The Path of the Righteous Gentile: An Introduction to the Seven Laws of the Children of Noah by Chaim Clorfene and Yaakov Rogalsky, that covers the issue. Here appears to be an online version of the book, but I can't vouch for the website. I couldn't find where he explicitly mentions this, but the feeling I got from it is that a gentile should simply believe in the God of the Torah. In Chapter 4 he describes various things that one "must realize" or "should contemplate" that basically explain the understanding of the omnipotence, mercy, and other qualities of God.

In Chapter 6 of the book, he details the laws against idolatry. In the beginning there, he explains that just by avoiding idolatry, he demonstrates belief in God.