In the spirit of YeHoshua Ha Mashiach!  - MOUNT MOREH-YAH : The mountain where YeHoVaH is Our Teacher

                      Sabbath Day And Not Sunday
 
Exodus 20:8-9: "Remember the Sabbath day, to keep it holy, Six days shalt thou labour, and do all thy work."   YeHoVah rested on the Sabbath day and blessed it from the very beginning. It was given to Adam. (Gen 2:1-3), it is called The Sabbath of YHVH." (Lev 23:3). Not the Jewish Sabbath because it belongs to YHVH. The Sabbath rest existed before Noah, Abraham and Moses, It was given to Adam.
 
Notices that only the seventh day Shabbat was given to us as a day of rest  we are commanded to work the other six days, Sunday is a work day, but  Many Christians have been wrongly taught that the Sabbath has changed to Sunday. Yahweh rested on the seventh day this is an unchangeable fact. The Sabbath day was the only day that Yahweh blessed and sanctified the seventh day.
Yahweh did not rest on the first day of the week so our weekly Shabbat (which commemorates His rest) can never be changed to Sunday. Yahweh worked on Sunday, the first day as he commands us also. The only Sabbath that was recognized in Scripture was the seventh day, Sunday was always referred to as the first day of the week in Scripture it was never called a Sabbath or the Lord's Day.
The concept of making Sunday into a replacement for the seventh day Shabbat comes from manmade traditions that lack any Scriptural support. The early church and apostles observed Shabbat:
 
"Now when Paul and his company loosed from Paphos, they came to Perga in Pamphylia: and John departing from them returned to Jerusalem. But when they departed from Perga, they came to Antioch in Pisidia, and went into the synagogue on the sabbath day, and sat down." Acts 13:14 "
And when the Jews were gone out of the synagogue, the Gentiles besought that these words might be preached to them the next sabbath. Now when the congregation was broken up, many of the Jews and religious proselytes followed Paul and Barnabas: who, speaking to them, persuaded them to continue in the grace of God. And the next sabbath day came almost the whole city together to hear the word of God." Acts 13:42-44
"And on the sabbath we went out of the city by a river side, where prayer was wont to be made; and we sat down, and spake unto the women which resorted thither." Acts 16:13 "And Paul, as his manner was, went in unto them, and three sabbath days reasoned with them out of the scriptures," Acts 17:2 "And he reasoned in the synagogue every sabbath, and persuaded the Jews and the Greeks." Acts 18:4
 
Notice in the above passages that some Gentiles/Greeks (non believers) were also observing the Sabbath and attending synagogue. It was never mention in The Brit Chadasha (New Testament) that the Sabbath day has changed to Sunday. Below are few passages that have been used incorrectly by the church to argue a Saturday-to-Sunday changeover, let's examine each one:
 
 "And upon the first day of the week, when the disciples came together to break bread, Paul preached unto them, ready to depart on the morrow; and continued his speech until midnight. Acts 20:7
 
Now, the problems in making this about a Sunday worship service like those the church has today. What is this service to break bread? First off, this is occurring Saturday evening not Sunday morning. Remember biblical days begin at sundown and continue until the following sundown.
 
 ("And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day." Genesis 1:5).
 
So here it is the first day of the week and it is evening. Since they are 'breaking bread' it seems clear they were gathered together for Havdalah services, (Havdalah, literally 'separation' - a ceremony involving bread, wine and spices which marks the ending of Shabbat). Havdalah begins Saturday at sunset, and clearly the disciples all met together for this service and then Sha'ul preached for them until midnight. Realize that this wasn't until midnight Sunday evening but midnight  Saturday evening Now travel distances exceeding 2000 cubits (approx half-mile) were forbidden on the Sabbath (referenced in Acts 1:12), so Sha'ul is planning to travel (to 'depart on the morrow,') on Sunday morning. Sha'ul would never make travel plans for Shabbat because he observed the Torah (Acts 24:14; 25:8; 28:17). This passage does not show Shabbat was changed to Sunday, it merely shows that the post-Sabbath observance of Havdalah was observed by the disciples.
 
"Upon the first day of the week let every one of you lay by him in store, as God hath prospered him, that there be no gatherings when I come." 1 Corinthians 16:2
 
Sha'ul is requesting here that donations should be set aside on the first week, Sunday. This money was be gathered ahead of time so that when Sha'ul arrived, the money would be ready to take to the saints in Jerusalem for distribution. Business matters (esp regarding money) are not conducted on G-d's Sabbath, so any collecting of this sort would have to be done Sunday through Friday. The Sabbath is not the topic here donations for the saints is. Nothing in this passage indicates a Sunday worship service, this is a practical matter about collecting money not about replacing G-d's Sabbath with a Sunday collection service!
 
"I was in the Spirit on the Lord's day, and heard behind me a great voice, as of a trumpet," Revelation 1:10
 
 "L-rd's Day" here is not referring to a specific day of the week; the Greek word here is Kuriokos (Strong's 2960) derived from Kurios (Strong's 2962) a verb meaning "supreme in authority" "G-d, Lord" "Master" or "Sir." Which day of the week is no where indicated in the text -- it is simply a 'Lordly Day," because it was a day the L-rd chose to make this revelation to John. No where in the Brit Chadasha is there any leap that Sunday is another name for the L-rd's Day.
 
"But pray ye that your flight be not in the winter, neither on the Sabbath day" Matthew 24:20
 
What difference would it make if the flight were on the Sabbath day if it were no longer binding?
 
"I am YHVH your God; walk in my statutes, and keep my judgments, and do them; and hallow my Sabbaths; and they shall be a sign between me and you, that ye may know that I am YHVH your God." Ezekiel 20:19, 20
 
The only true G-d, YHVH, says to remember His Sabbaths. Why does man always go after counterfeits? Scripture names our days by their number, 'first' through 'seventh,' with the seventh day having the distinction of being the Sabbath. Sunday is a later name given to the first day of the week and it indicates that particular day's pagan dedication. 'Sunday' refers to worship of the sun-god. In The Two Babylon’s Alexander Hislop explains:
 
"The sun, as the great source of light and heat, was worshipped under the name Ba'al. Now the fact that the sun, under that name, was worshipped in the earliest ages of the world shows the audacious character of these first beginnings of apostacy. Men have spoken as if the worship of the sun and of the heavenly bodies was a very excusable thing to do, into which the human race might very readily and very innocently fall."
 
 Compare to II Kings 23:5: "And he put down the idolatrous priests, whom the kings of Judah had ordained to burn incense in the high places in the cities of Judah, and in the places round about Jerusalem; them also that burned incense unto Baal, to the sun, and to the moon, and to the planets, and to all the host of heaven."
 
 Many ancient pagan sites were originally established for sun-worship the pyramids of Giza, Stonehenge, and numerous pagan temples were dedicated to Helios, Apollo, and Mithras. Even Israel went astray into sun-worship: "
 
And hath gone and served other gods, and worshipped them, either the sun, or moon, or any of the host of heaven, which I have not commanded;"Deuteronomy 17:3
"And he brought me into the inner court of YHVH'S house, and, behold, at the door of the temple of the LORD, between the porch and the altar, were about five and twenty men, with their backs toward the temple of YHVH, and their faces toward the east; and they worshipped the sun toward the east."
 
Idolatry and Yahweh's Truth cannot mix. "Ye cannot drink the cup of the Lord, and the cup of devils: ye cannot be partakers of the Lord's table, and of the table of devils." 1 Corinthians 10:21
 
It is very dangerous for man to rationalize such observances with but most so called Christian will say “but we don't worship on Sunday for the sun-god we do it for the true G-d, Yahweh." Yahweh commands His people to not to follow pagan observances. No matter how clever man may attempt to rationalize the observances to make them seem godlier, what is contrary to Yahweh remains contrary to Yahweh. Both Cain and Abel made offerings to G-d but Yahweh only accepted the appropriate offering. It's the same with our Sabbath day; Yahweh determines which day is acceptable to Him, Not man.
 
"For in six days the LORD made heaven and earth, the sea, and all that in them is, and rested the seventh day: wherefore the LORD blessed the Sabbath day, and hallowed it." Exodus 20:11 "Wherefore the children of Israel shall keep the Sabbath, to observe the Sabbath throughout their generations, for a perpetual covenant." Exodus 31:16