Henotheism

Henotheism is a temporary form of monotheism that places exclusive devotion on a single Deity, worshipped as the one and only God for a short period of time; it could be best explained as the "belief in individual gods appearing alternatively as the highest gods". Henotheism is confused with monolatry sometimes, but they are different concepts of religious belief.

History
The term Henotheism was originally coined in 1860 by Friedrich Max Müller, a German Indologist, philologist and historian of comparative religion. Müller applied it to the temporany, ritual and liturgical worship of one single God at a time, especially in Vedas; thus, is a form of devotion that was practiced by Hindus only. He employed it in conjunction with the term Kathenotheism in order to distinguish Hinduism ( in particular) from Greco-Roman polytheism and Abrahamic monotheisms, and present Hindu beliefs in a more comprehensible way to European scholars that knew nothing of Eastern religious traditions.

The distinction between monotheism and henotheism was stated by Müller as follows: If therefore, an expression had been given to that primitive intuition of the Deity which is the mainspring of all later religions, it would have been - There is a god, but not yet There is but One God. The latter form of faith, the belief in One God, is properly called Monotheism, whereas the term of Henotheism would best express the faith in a single god.

Afterwards, his contemporary religious scholars (among them, his colleagues) tried to give a more precise definition of the term, and its correlation to monotheism and monolatry; aside from slight differences, they all agreed with Müller that henotheism is a legitimate but nonetheless temporany form of monotheism. However, both the terms Henotheism and Kathenotheism have soon become obsolete, and hardly survived criticism from late academics.

Hebrew Bible
We can see the last stages of the evolution from henotheism to monolatry, and finally from monolatry to monotheism within the pages of the Hebrew Bible itself. At first the Hebrews practiced henotheism as seen in the commandment by Yahweh/El to have "no other gods before me", which only makes sense if other gods are held to exist. When one god possesses much greater power and authority than all the other gods combined, researchers call the religion a henotheism. A henotheism stands between polytheism (in which there are many gods, each with relatively equal power and authority) and monotheism (in which there is one god and no other supernatural agents of any kind). In the ancient Near East, every patron god was the divine king in a henotheism, and all other gods were subordinate to him. In most henotheisms, humans were permitted to worship many gods, but the patron remained in charge. This approach offered the human king a practical advantage. The king could permit the gods of popular piety a place in the divine realm without taking the risk that one of these alternate gods might threaten his own religious and political supremacy. Henotheism was a religious umbrella under which every god, no matter how minor, could find a place. On rare occasions, so-called intolerant henotheism was imposed. In this case, worship of lesser gods was prohibited and the patron god alone received worship. Some researchers call this intolerant henotheism a monolatry, which means "worship of only one". Many portions of the Bible express monolatry. For example, when Yahweh declares that he is a jealous god who banishes all other gods from his presence, the author of this commandment does not deny that other gods exist but prohibits worship of them. Likewise, when Micah announces that other kingdoms will walk "each in the name of its god", but Israel will walk in the name of Yahweh, Micah does not deny that other gods might be real. After the Hebrews became fully monotheistic around the time of the Babylonian Captivity, and Yahweh started to be regarded as the only One God of Israel, the injunction against idolatry remained in the Scriptures as an admonishment: according to the Israelites, to worship other people's gods in foreign lands meant to abandon their national God and the Land of Israel. Thus, Jewish monotheism was the outcome of this process of isolation and stabilization of their ethno-religious identity during the Exile.

Christianity
Christianity, which retains the Old Testament as scripture, also condemns idolatry and explains this peculiarity by merging all Baal worship or Marduk worship (or even the veneration of Mary, according to Protestants) into Satan worship. That way the commandment from God not to worship other gods is not tacit acknowledgment of the existence of other gods, but simply God trying to keep people from being snared by the wiles of the Devil.

Mormonism
Mormonism's doctrine that God the Father is but one of many Gods shares a few similarities with henotheism, but is distinguished from it by the the absence of recognition of other gods (including resurrected humans granted their own universe over which to rule) in any devotional sense - only God the Father, and God the Son Jehovah/Jesus Christ are held to be worthy of devotion.

Moreover, Mormons have been frequently criticized by other Christians (mostly Trinitarians) because they don't accept the Trinity as it was established in the Nicene Creed; Mormons are more prone to define their conception of the Godhead as a "social" interrelation between God the Father (the "Supreme Being" and "Creator"), God the Son and Holy Ghost: they all form the Godhead, but they're also autonomous and distinct Persons; the Father and the Son have physical bodies, whereas the Holy Ghost has a spiritual one  (this definition of the Triune God has been accused of "Tritheism"). Thus, Mormons are charged with heresy by some Trinitarian Churches.