As Tall73 is impressed by masive cut and paste:
Here are the words of Protestant luminaries Martin Luther and John Calvin
who both wrote against people who worship only on a Saturday...
http://www.cryingvoice.com/Endtimes/Sabbath3.html
Luther Against the Sabbatarians Martin Luther
Against the Sabbatarians: Letter to a Good Friend
1538
Introduction
"The term 'Sabbatarians' has been used to refer to a number of movements,
occurring in various epochs of church history, which have as their common
denominator an insistence on a return by Christians to the essentials of
Jewish Sabbath observance. Usually they are also characterized by an
intense eschatological expectation, together with an inclination toward
literalism in the interpretation of both the Old and the New Testaments."
"In view of Luther's emphasis on Christian freedom, based on a clear
distinction between law and gospel, it was predictable that he would
vigorously oppose the Sabbatarian position. What gives special point to
Luther's treatise is his assumption that Jewish agitation and efforts at
proselytization lay at the root of the movement."
Against the Sabbatarians: Letter to a Good Friend
In the first part of his letter Luther proves that Jews are wrong in their
expectations and that Jesus Christ was the promised Messiah. We have
selected those parts from Part Two which deal with the Ten Commandments in
general and the commandment concerning the Sabbath in particular.
Part Two
...Finally, we also want to discuss the Ten Commandments. For perhaps the
Jews will also call the Ten Commandments the law of Moses, since they were
given on Mount Sinai in the presence of none but the Jews or children of
Abraham, etc. You must reply: If the Ten Commandments are to be regarded
as Moses' law, then Moses came far too late, and he also addressed himself
to far too few people, because the Ten Commandments had spread over the
whole world not only before Moses but even before Abraham and all the
patriarchs. For even if a Moses had never appeared and Abraham had never
been born, the Ten Commandments would have had to rule in all men from the
very beginning, as they indeed did and still do.
For all creatures rightly regard God as God and honor his name, as do also
the angels in heaven. Thus we and all human beings are obligated to hear
his word, to honor father and mother, to refrain from killing, from
adultery, from stealing, from bearing false witness, from coveting one's
neighbor's house or anything else that is his. All the heathen bear
witness to this in their writings, laws, and governments, as can be
clearly seen; but nothing is said therein of circumcision or the laws
Moses gave to the Jews for the land of Canaan.
Moses did precede all other legislators, however, in revealing in his
history the genesis of all creatures and the coming of death into the whole
world through Adam's fall or sin. And later when he wants to set up a
special law and nation apart from all others, as he has been commanded to
do, he first introduces God himself; he is the universal God of all the
nations, who gives the universal Ten Commandments—which prior to this had
been implanted at creation in the hearts of all men—to this particular
people orally as well. In his day Moses fitted them nicely into his laws
in a more orderly and excellent manner than could have been done by anyone
else. Circumcision and the law of Moses, however, were not implanted in
men's hearts; they were first imposed by Abraham and Moses on their
people...
...Similarly, the third commandment concerning the Sabbath, of which the
Jews make so much, is per se a commandment that applies to the whole world;
but the form in which Moses frames it and adapts it to his people was
imposed only on the Jews, just as with regard to the first commandment
none but the Jews must believe and confess that the common God of all the
world led them out of Egypt. For the true meaning of the third commandment
is that we on that day should teach and hear the word of God, thereby
sanctifying both the day and ourselves. And in accord with this, ever
after to the present day, Moses and the prophets are read and preached on
the Sabbath day among the Jews. Wherever God's word is preached it follows
naturally that one must necessarily celebrate at the same hour or time and
be quiet, and without any other preoccupation only speak and hear what God
declares, what he teaches and tells us.
Therefore everything depends completely on this, that we sanctify the day.
This is more important than celebrating it. For God does not say: You
shall celebrate the holy day or make it a Sabbath—that will take care of
itself. No, you shall sanctify the holy day or Sabbath. He is far more
concerned about the sanctifying than about the celebrating of it. And
where one or the other might be or must be neglected, it would be far
better to neglect the celebrating than the sanctifying, since the
commandment places the greater emphasis on the sanctifying and does not
institute the Sabbath for its own sake, but for the sake of its being
sanctified. The Jews, however, lay greater emphasis on the celebrating than
on the sanctifying (which God and Moses do not do) because of the
additions they have made.
Moses' mention of the seventh day, and of how God created the world in six
days, which is why they are to do no work—all this is a temporal
adaptation with which Moses suits this commandment to his people,
especially at that time. We find nothing written about this previously,
either by Abraham or at the time of the old fathers. This is a temporary
addendum and adaptation intended solely for this people which was brought
out of Egypt. Nor was it to endure forever, any more than was the whole
law of Moses. But the sanctifying—that is, the teaching and preaching of
God's word, which is the true, genuine, and sole meaning of this
commandment—has been from the beginning and pertains to all the world
forever. Therefore the seventh day does not concern us Gentiles, nor did
it concern the Jews beyond the advent of the Messiah, although by the very
nature of things one must, as already said, rest, celebrate, and keep the
Sabbath on whatever day or at whatever hour God's word is preached. For
God's word cannot be heard or taught when one is preoccupied with
something else or when one is not quiet.
Therefore Isaiah, too, declares in chapter 66 [:23] that the seventh day,
or, as I call it, Moses' adaptation of it, will cease at the time of the
Messiah when true sanctification and the word of God will appear richly.
He says that there will be one Sabbath after another and one new moon
after another, that is, that all will be sheer Sabbath, and there will no
longer be any particular seventh day with six days in between. For the
sanctifying or the word of God will enjoy full scope daily and abundantly,
and every day will be a Sabbath...
http://www.cryingvoice.com/Endtimes/Sabbath2.html
Calvin Refutes Sabbath-keeping John Calvin
Institutes of the Christian Religion
Translated by Henry Beveridge
Volume 2.
Chapter 8. Exposition of the Moral Law. Fourth Commandment.
Remember the Sabbath day to keep it holy. Six days shalt thou labour and
do all thy work: but the seventh day is the sabbath of the Lord thy God.
In it thou shalt not do any work, &c.
28. The purport of the commandment is, that being dead to our own
affections and works, we meditate on the kingdom of God, and in order to
such meditation, have recourse to the means which he has appointed. But as
this commandment stands in peculiar circumstances apart from the others,
the mode of exposition must be somewhat different. Early Christian writers
are wont to call it typical, as containing the external observance of a
day which was abolished with the other types on the advent of Christ. This
is indeed true; but it leaves the half of the matter untouched. Wherefore,
we must look deeper for our exposition, and attend to three cases in which
it appears to me that the observance of this commandment consists. First,
under the rest of the seventh days the divine Lawgiver meant to furnish the
people of Israel with a type of the spiritual rest by which believers were
to cease from their own works, and allow God to work in them. Secondly he
meant that there should be a stated day on which they should assemble to
hear the Law, and perform religious rites, or which, at least, they should
specially employ in meditating on his works, and be thereby trained to
piety. Thirdly, he meant that servants, and those who lived under the
authority of others, should be indulged with a day of rest, and thus have
some intermission from labour.
29. We are taught in many passages that this adumbration of spiritual rest
held a primary place in the Sabbath. Indeed, there is no commandment the
observance of which the Almighty more strictly enforces. When he would
intimate by the Prophets that religion was entirely subverted, he
complains that his sabbaths were polluted, violated, not kept, not
hallowed; as if, after it was neglected, there remained nothing in which
he could be honoured. The observance of it he eulogises in the highest
terms, and hence, among other divine privileges, the faithful set an
extraordinary value on the revelation of the Sabbath. In Nehemiah, the
Levites, in the public assembly, thus speak: "Thou madest known unto them
thy holy sabbath, and commandedst them precepts, statutes, and laws, by
the hand of Moses thy servant." You see the singular honour which it holds
among all the precepts of the Law. All this tends to celebrate the dignity
of the mystery, which is most admirably expressed by Moses and Ezekiel.
Thus in Exodus: "Verily my sabbaths shall ye keep: for it is a sign
between me and you throughout your generations; that ye may know that I am
the Lord that does sanctify you. Ye shall keep my sabbath therefore; for
it is holy unto you: every one that defileth it shall surely be put to
death: for whosoever does any work therein, that soul shall be cut off
from among his people. Six days may work be done; but in the seventh is
the sabbath of rest, holy to the Lord: whosoever does any work in the
sabbath day, he shall surely be put to death. Wherefore the children of
Israel shall keep the sabbath, to observe the sabbath throughout their
generations, for a perpetual covenant. It is a sign between me and the
children of Israel for ever," (Exodus 31:13—17.) Ezekiel is still more
full, but the sum of what he says amounts to this: that the sabbath is a
sign by which Israel might know that God is their sanctifier. If our
sanctification consists in the mortification of our own will, the analogy
between the external sign and the thing signified is most appropriate. We
must rest entirely, in order that God may work in us; we must resign our
own will, yield up our heart, and abandon all the lusts of the flesh. In
short, we must desist from all the acts of our own mind, that God working
in us, we may rest in him, as the Apostle also teaches. (Heb. 3:13;
4:3,9.)