Given how your previous lists of copied and pasted quotes in this topic turned out (see
here and
here, where I showed that virtually everything in them was misrepresented or irrelevant), it's not clear to me why we should be trusting this new one.
Still, let's take a look at it.
We run into immediate problems with this. First, you declare that the first day of the week was dedicated to Bel/Marduk and the calendar was adjusted so the first day of every month was also the first day of the week. Yet you decline to offer any evidence that the first day of the month was also the first day of the week. The quote you offer says nothing about it. I don't think the book being cited says it either; certainly, the page being cited doesn't. Your already tenuous claim this has anything to do with Sunday worship in Christianity collapses completely without the first day of the month also being the first day of the week, yet you offer no evidence for it.
Second, your quote isn't the full sentence. The full sentence reads: "It is clear that the first day of the month was originally a day of rest and fasting: so were days 7, 9, 14, 19, 21, 28, 29, 30." So even if we suppose that the first day of the month was always the first day of the week (which again you cited no evidence for), it's only one of nine days of the month to do have the rest/fasting, and more than any others are the
sixth day of the week. So even if this claim of yours is true... this would actually be evidence in favor of Jews taking the idea of the sixth day being holy and important from the Babylonians! Your source even suggests this Babylonian practice may have been the origin of the Jewish Sabbath. Are you making that claim?
There's an interesting sleight of hand here; it says the name Sunday came from Egyptian astrology, then tries to associate that with Ra, even though... no evidence is actually given that Sunday was of particular importance to the Egyptians, or even that Ra worship had any association with Sunday.
The "Medo-Persian" is wrong. See, Franz Cumont was a writer about Mithraism, and was very influential. Unfortunately, various claims he made that were speculations were taken as fact, and it was a while before people started to be more critical of some of his ideas (unfortunately, some continue to repeat uncritically his ideas). So he's an out of date source.
Now, there were two Mithras. One was the earlier Persian one, and the other was the later Roman one. Cumont was a strong believer that they were basically the same deity, so he would take things from the Roman Mithra and suppose it was true about the Persian Mithra, without any real warrant. This idea has been largely abandoned, viewing the two as rather distinct deities, without much transferring over from one to the other (as I saw someone amusingly say, the two Mithras were different enough that one would be tempted to conclude he had a mid-life crisis). Thus, his claim that Sunday was important to Mithraism doesn't back-date it to the Persian Mithra.
Another claim Cumont made, which is maddeningly repeated uncritically, is that December 25 was the birthday of Mithra. However, this was really just a speculation on Cumont's part, as
this page explains fairly well. And I can't help but notice that when people claim Mithraism considered Sunday to be particularly holy, it seems to always be people who make the incorrect December 25 claim alongside it! The Sunday claim was made by Cumont doesn't offer any citation for the Sunday claim--at least, not in the English version of the book--and no one else seems to. So, I'd like to ask for a
primary source that Sunday was in fact particularly sacred in Mithraism (preferably a source that predates Christian Sunday worship, or else it could have gone the other way), not merely Cumont and people just parroting Cumont's ideas. Granted, that wouldn't necessarily prove a connection, but it'd be a required first step. So let's see the primary source.
The actual name of the work is Alb
eruni's India. Ordinarily this would be a minor note, but the fact you didn't correct the error the place you copied and pasted all of this from is just evidence you didn't bother to verify it.
Also, the actual text differs slightly from what is offered by the quote. It says "The single days enjoy different degrees of veneration according to certain qualities which they attribute to them. They distinguish, e.g., the Sunday, because it is the day of the sun and the beginning of the week, as the Friday is distinguished in Islam." Admittedly, there is little difference in meaning, and unlike other cases in this list where I showed that the quotes were apparently edited to conceal information--but it's still an error.
Anyway, this quote doesn't say Sunday was a "holy day", or at least any holier than any other day. It just says they have different qualities attributed, and it says as an
example that Sunday is distinguished by being the day of the sun and the beginning of the week. It says nothing about it getting higher reverence at all.
Notice how desperate this claim it; it says nothing of Sunday, merely that Buddha is "reported" to have been of solar descent, which even if true doesn't prove anything. Also, Buddhism was so far separated geographically and linguistically from the early church that it's fairly silly to try to draw connections between them.
An oddity is that it says "Koreans". Buddhism didn't originate from Korea (it came from India, but I guess the person who came up with these quotes had already used that one), and as far as I can tell it only made its way there in the later fourth century AD. This indicates ignorance on the part of the person who came up with these quotes. Perhaps the source explicitly said it was talking specifically about Korean Buddhist beliefs (I was unable to check the source for context), but if that's the case then the lateness means this already irrelevant quote somehow manages to become even more irrelevant because of the date it was introduced.
A work from the the 17th century that makes a vague, brief, uncited claim that they had "peculiar adoration to the sun" on Sunday is not exactly what one would call particularly strong evidence that they actually viewed Sunday as particularly important in a religious sense.
First day of every month ≠ first day of the week. Also, your quote deceitfully edits what the work
actually says: "At Sparta on the first
and seventh days of every month the kings sacrificed to Apollon... At Athens the first
and seventh days of every month were sacred to Apollon." (the ellipsis just cuts out some in-line citations) Aside from the paraphrasing regarding Athens, one finds it rather interesting that your quote chooses to ignore the fact the
seventh day of the month was also important in this.
As discussed earlier, the idea that Mithra's birthday was December 25 was a
speculation that Franz Cumont had, but which is not attested anywhere--or, at least, no one has ever been able to point to any attestation of it. While the source relying on Cumont is a bit understandable given that for a while he was the main person who actually wrote about Mithra so people had to take information from him, it shows it's out of date, and it repeating a speculation as fact means there's not much reason to take its other claims as accurate either. So, again: Can you offer a
primary source for Mithraists finding Sunday to be particularly holy?
This has the same problem as the above, but is even worse. You see, the above quote cuts off mid-sentence:
"It had so much acceptance that it was able to impose on the Christian world its own Sun-Day in place of the Sabbath, its Sun's birthday, 25th December, as the birthday of Jesus; its Magi and its Shepherd hailing the divine star, and various of its Easter celebrations."
We've already discussed how the issues with the December 25 and Sunday claims. The claim of Easter celebrations is too vague to assess, but seems dubious. And the "Magi and its Shepherd hailing the divine star" is wrong too. But since you apparently trust the source so much, are you going to adopt the idea that the Magi and Shepherds in the Bible are just taken from Mithraism?
Well, it shows people should be cautious trusting a bunch of unverified quotes that are just copied and pasted.