Lewis lists these groups as having in common with Christianity the belief in gods or God. What is each group's view of Deity?
Ancient Greece existed from roughly 750 BC to AD 529. Greek gods included Zeus and Hera, Ares, Aphrodite, Hades, and so on. The Apostle Paul addressed Greek beliefs regarding their gods when he spoke to the Athenians on the Areopagus, also known as Mars Hill, in Acts 17:16-23.
Now while Paul was waiting for them at Athens, his spirit was provoked within him as he saw that the city was full of idols. So he reasoned in the synagogue with the Jews and the devout persons, and in the marketplace every day with those who happened to be there. Some of the Epicurean and Stoic philosophers also conversed with him. And some said, "What does this babbler wish to say?" Others said, "He seems to be a preacher of foreign divinities"—because he was preaching Jesus and the resurrection. And they took him and brought him to the Areopagus, saying, "May we know what this new teaching is that you are presenting? For you bring some strange things to our ears. We wish to know therefore what these things mean." Now all the Athenians and the foreigners who lived there would spend their time in nothing except telling or hearing something new.
So Paul, standing in the midst of the Areopagus, said: "Men of Athens, I perceive that in every way you are very religious. For as I passed along and observed the objects of your worship, I found also an altar with this inscription, 'To the unknown god.' What therefore you worship as unknown, this I proclaim to you. . . .”
Ancient Rome started in 753 BC and began to decline around AD 190. Roman gods borrowed their attributes from Greek gods; they included Jupiter, Neptune, Apollo, and Mars.
In general the term "savage" refers to someone from a "primitive," nonliterate society. In Christian terminology it is often a synonym for "pagan." The term "savage" has fallen out of favor today (see "Anthropology" here); such people groups are more likely to be defined as "indigenous peoples," "hunter-gatherer societies," or "tribes." Their religious beliefs tend to be characterized by animism, nature worship, and pantheism.
According to the Stanford Encyclopedia of Philosophy, "The Stoic God is immanent throughout the whole of creation and directs its development down to the smallest detail" and is akin to the idea of "fate."
Plato's view of the gods was at odds with that of the Greeks. Based on statements made in The Republic, we can assume Plato thought of the gods as being "perfect beings, with perfect bodies, far more beautiful than our own; they cannot be killed--in fact, they cannot be harmed in any way. Their bodies are incorruptible. What is more, since they do not die, they need not replenish their population; thus they do not beget child gods" ("Did Socrates Teach New Deities?" Dr. Jan Edward Garrett). Dr. Garrett, of Western Kentucky University, has put together a helpful chart regarding the attributes of Plato's gods, which can be found here.
For information on Hindu beliefs, see the first Bookmark for page 6.
This is Lewis's term for Muslims, followers of Islam. It is now considered an offensive term, although in Lewis's time and in his circles no offense was intended.
According to allah.org, "Allah is the personal name of the One true God. Nothing else can be called Allah. The term has no plural or gender. This shows its uniqueness when compared with the word god which can be made plural, gods, or feminine, goddess. It is interesting to notice that Allah is the personal name of God in Aramaic, the language of Jesus and a sister language of Arabic.
"The One true God is a reflection of the unique concept that Islam associates with God. To a Muslim, Allah is the Almighty, Creator and Sustainer of the universe, Who is similar to nothing and nothing is comparable to Him. The Prophet Muhammad was asked by his contemporaries about Allah; the answer came directly from God Himself in the form of a short chapter of the Quran, which is considered the essence of the unity or the motto of monotheism. This is chapter 112 which reads:
"'In the name of God, the Merciful, the Compassionate. Say (O Muhammad) He is God the One God, the Everlasting Refuge, who has not begotten, nor has been begotten, and equal to Him is not anyone.'"