Genesis 2:2-3
2 And on the seventh day God ended his work which he had made; and he rested on the seventh day from all his work which he had made.
3 And God blessed the seventh day, and sanctified it: because that in it he had rested from all his work which God created and made.
Ex 20:11 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.
Ex 23:12 Six days thou shalt do thy work, and on the seventh day thou shalt rest: that thine ox and thine ass may rest, and the son of thy handmaid, and the stranger,
may be refreshed.
Ex 31:16
16 Wherefore the children of Israel shall keep the
sabbath, to observe the sabbath throughout their generations, for a perpetual covenant.
Lev 23:3 Six days shall work be done: but the seventh day is the sabbath of rest, an holy
convocation; ye shall do no work therein: it is the sabbath of the LORD in all your dwellings.
Deut 5:12-13
12 Keep the sabbath day to sanctify it, as the LORD thy God hath commanded thee.
13 Six days thou shalt labour, and do all thy work:
Isa 58:13 If thou turn away thy foot from the sabbath, from doing thy pleasure on my holy day; and call the sabbath a delight, the holy of the LORD, honourable; and shalt honour him, not doing thine own ways, nor finding thine own pleasure, nor speaking thine own words:
Jer 17:21-22
21 Thus saith the LORD; Take heed to yourselves, and bear no burden on the sabbath day, nor bring it in by the gates of Jerusalem;
22 Neither carry forth a burden out of your houses on the sabbath day, neither do ye any work, but hallow ye the sabbath day, as I commanded your fathers.
Ezek 20:12 Moreover also I gave them my sabbaths, to be a sign between me and them, that they might know that I am the LORD that sanctify them.
Luke 23:56
56 And they returned, and prepared spices and ointments; and rested the sabbath day according to the commandment.
The Sabbath or Shabbat is to be a day of Rest. Rest from all types of work or labour. It is suppose to be a day of doing good to others. Helping the needy and widow, healing or assisting the sick, along with prayer and worship of God and reading His Word. The Sabbath is to rest but also to point to the future during which Jesus/Yeshua will bring in the eternal day of rest.
In the New Heavens and New Earth we will observe new moons and Sabbaths.
Isa 66:22-23
22 For as the new heavens and the new earth, which I will make, shall remain before me, saith the LORD, so shall your seed and your name remain.
23 And it shall come to pass, that from one new moon to another, and from one sabbath to another, shall all flesh come to worship before me, saith the LORD.
KJV
The changing of the sabbath from Saturday to Sunday, was done by early church fathers of the Roman Catholic Church (RCC) who claims they have the right to make such a change. The change was done according to verses in the New Testament.
Matt 28:1 In the end of the sabbath, as it began to dawn toward the first day of the week, came Mary Magdalene and the other Mary to see the sepulchre.
Mark 16:1-2
1 And when the sabbath was past, Mary Magdalene, and Mary the mother of James, and Salome, had bought sweet spices, that they might come and anoint him.
2 And very early in the morning the first day of the week, they came unto the sepulchre at the rising of the sun.
Luke 24:1 Now upon the first day of the week, very early in the morning, they came unto the sepulchre, bringing the spices which they had prepared, and certain others with them.
John 20:1 The first day of the week cometh Mary Magdalene early, when it was yet dark, unto the sepulchre, and seeth the stone taken away from the sepulchre.
This is where we have been told we get the change of sabbath days. However, there is no verbatim command set down by Yeshua/Jesus, or by the disciples or the apostles that says anything about a change of Sabbath. In the book of Acts it is recorded that Paul held services on Sabbath even for the Gentiles.
Acts 13:14 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 13:27 For they that dwell at Jerusalem, and their rulers, because they knew him not, nor yet the voices of the prophets which are read every sabbath day, they have fulfilled them in condemning him.
Acts 13:42 And when the Jews were gone out of the synagogue, the Gentiles besought that these words might be preached to them the next sabbath.
Acts 13:44 And the next sabbath day came almost the whole city together to hear the word of God.
Acts 16:13 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 17:2 And Paul, as his manner was, went in unto them, and three sabbath days reasoned with them out of the scriptures,
Acts 18:4 And he reasoned in the synagogue every sabbath, and persuaded the Jews and the Greeks.
Paul after his conversion went to the synagogue to preach and the Greeks came there to hear him. Why not start a 'church' for the Greeks? Because God did not want us to separate but to be united. He wants us to go by His commandments not man made commandments. The Greeks understood this at the time, but as the Greeks and other nationalities conversions grew they went their own way and started their own places of worship and wanted to get away from God and His People.
Click here for a Typical Jewish Sabbath