Greetings. I appreciate the input. Based on the information I have obtained over the last 10-15 years, I don't think history supports your view. I will, of course, hear you out but until you provide "Scripture" that reveals a move to Sunday, I can't see leaving the day that was set apart. That said....
There is no doubt that some Jews began to keep Sunday immediately. However, as stated, you won't find a mandate in Scripture to do so. In your first attempt to show my error, you didn't share any Scripture that states that Sunday would be set-apart for the Christian, you showed the Epistle of Barnabas which is neither canon nor 100% trustworthy.
I am certain you are familiar with the fast of the first born? For those who aren't, this is a fast that began on the evening of the 14th of Nisan, Passover. Keep in mind, the day begins at sundown so this would have been the night before Yeshua was killed... however, by biblical counting it is still the same day. Anyway, the first born male, by tradition, would fast from the evening of the 14th until the evening of the 15th which was the beginning of Unleavened Bread and also when the Passover Lamb would be eaten. However, some first born males, including James, continued their fast until Sunday when it was learned that Yeshua had risen. A very small number of Jews began to observe Sunday at that time because of the spiritual significance of that day as they perceived it. This practice was in strict minority until a much later time.
There are two events that did come later that really define the course of the church. The first was the death of James (who was the head of the church at Jerusalem) and the destruction of the Temple (they happened close in time so I count them as one)... and this event was something that many Jews believed was Yeshua's warning (Matthew 24:15-16) and thus as many as half of the Jewish Christians fled to the mountains. The remaining half stuck it out, reproduced, and grew in number until the Bar Khokba revolt. There, Rabbi Akiva gave Bar Kosiba a messianic title in an effort to rally the Jews against the Romans. The remaining Jewish Christians would not fight for the sovereignty of their homeland under the banner of a false messiah, and they too fled the area. From that point on, within just 20 years (by 150AD...ish), the face of Christianity, the visible open face, was more Greek than Jewish. Animosity that began with the actions of the Pharisees, took on a fever pitch by the Greek Christians and the Jews began to be called "Christ-Killers" (Justin Martyr around 150AD in “Dialogue with Trypho”) and were maligned in other ways as seen in the homily Peri Pascha, Melito of Sardis (circa middle of the second century) where it was stated, “God was murdered” by the Jews, of course. These writings and MANY MORE I can produce, set the tone for our paradigm and as we move forward in time, this becomes the mindset of Christians and is what we are “born into” which shapes how we view Scripture as we read it. That is really important but rarely considered... if a decision is made or a conclusion reached and is accepted by the religious culture... then any dissension is lost after the opposing generation dies off. We are 1600-1700 YEARS after many decrees were passed that were designed to make us appear less Jewish. So, we are NOW "born into" a religious culture that has no Jewish connection at all EVEN IF Christianity was considered a sect of Judaism in the first century.
Anyway... back to 150AD...ish..... the Greeks who were becoming Christians had already been keeping Sunday (they were sun worshipers). And, since the Greeks tended to look for ways to spiritualize reality, the idea of setting Sunday aside because Yeshua was raised (really Saturday night) on that day was a natural fit for them and they began to do it in force. By the time The Council of Laodicea (canon 29) is made that prohibits resting on the “Jewish Sabbath,” it was already pretty much a foregone conclusion and the practice of the day. But we are now talking about more than 300 YEARS since the ascension. Look how much more liberally so many in our culture view the Constitution (and how much more so should HRC win) in just 240 years. When it comes to practice, what we are talking about is over 300 years and an entire CULTURE removed... no longer Jewish but Greek. No longer function but form.
Still, you will find NO Scripture that sets apart Sunday, none. Not only that, you will find Catholics claiming that they are responsible for the move, at least officially.
"It is well to remind the Presbyterians, Baptists, Methodists, and all other Christians, that the Bible does not support them anywhere in their observance of Sunday. Sunday is an institution of the Roman Catholic Church, and those who observe the day observe a commandment of the Catholic Church." Priest Brady, in an address reported in the Elizabeth, NJ News on March 18, 1903
"Protestants ... accept Sunday rather than Saturday as the day for public worship after the Catholic Church made the change... But the Protestant mind does not seem to realize that ... in observing Sunday, they are accepting the authority of the spokesman for the Church, the pope." Our Sunday Visitor, February 5, 1950
Which is the Sabbath day? Saturday is the Sabbath day. Why do we observe Sunday instead of Saturday? We observe Sunday instead of Saturday because the Catholic Church transferred the solemnity from Saturday to Sunday." Rev. Peter Geiermann C.S.S.R., The Convert's Catechism of Catholic Doctrine, p. 50
"Must not a sensible Protestant doubt seriously, when he finds that even the Bible is not followed as a rule by his co-religionists? Surely, when he sees them baptize infants, abrogate the Jewish Sabbath, and observe Sunday for which there is no Scriptural authority; when he finds them neglect to wash one another's feet, which is expressly commanded, and eat blood and things strangled, which are expressly prohibited in Scripture. He must doubt, if he think at all. ... Should not the Protestant doubt when he finds that he himself holds tradition as a guide? Yes, if he would but reflect that he has nothing but Catholic tradition for keeping the Sunday holy." Controversial Catechism, Stephen Keenan, New Edition, revised by Rev. George Cormack, published in London by Burns & Oates, Limited - New York, Cincinnati, Chicago: Benzinger Brothers, 1896, pp. 6-7
So, if you want to sway my view, show me SCRIPTURE that moves the Sabbath to Sunday or otherwise sets Sunday apart, makes it holy, from the other days. If man lives not by bread but by "every word of God," then show me in the Word of God where we set Sunday aside. I keep Saturday because I can find no mandate to move the Sabbath nor abolish it. Eve if you view it as "a shadow," what it points to have NOT come to pass yet. You will take communion (something first done in a Passover Sedar) and communion points BACK to something already completed, and then not take part in something that points to something that has yet to come to pass. I find that, personally, to be inconsistent.