Nowhere in Scripture is there any command for gentiles to keep the Saturday sabbath. And Paul, writing to the gentiles of Colosse, wrote in Col. 2:16, "Therefore do not let anyone judge you by what you eat or drink, or with regard to a religious festival, a New Moon celebration or a Sabbath day."
Meanwhile, back at the ranch...
The mark of the beast will likely be an implanted microchip that can hold all of one's financial records & dealings. Workers will be paid by having their funds added to the record in the chip. THE TECH ALREADY EXISTS; when the antichrist comes to power, he will soon make it compulsory.
When Jesus customarily went into the synagogue on the Sabbath day, he didn't go as a Jew, on behalf of the Jewish nation, but as the Son of man, as the second Adam, representing the entire race to God.
14 And Jesus returned in the power of the Spirit into Galilee: and there went out a fame of him through all the region round about.
15 And he taught in their synagogues, being glorified of all.
16 And he came to Nazareth, where he had been brought up: and, as his custom was, he went into the synagogue on the sabbath day, and stood up for to read.
17 And there was delivered unto him the book of the prophet Esaias. And when he had opened the book, he found the place where it was written,
18 The Spirit of the Lord is upon me, because he hath anointed me to preach the gospel to the poor; he hath sent me to heal the brokenhearted, to preach deliverance to the captives, and recovering of sight to the blind, to set at liberty them that are bruised,
19 To preach the acceptable year of the Lord.
20 And he closed the book, and he gave it again to the minister, and sat down. And the eyes of all them that were in the synagogue were fastened on him.
21 And he began to say unto them, This day is this scripture fulfilled in your ears.
This particular Sabbath Day, Jesus declared Himself to be, the long awaited for Messiah to Israel according to the prophecies in Isaiah. But the prophecies also show that He would give the light to the Gentiles as well.
Many see that the verses in Acts 13:42-44 confirm the truth, that Gentiles after their conversion to Christ, kept the Seventh Day holy. But many take for granted the surrounding verses referenced from the prophecies of Isaiah to show that it was foretold of the Gentiles worshipping on the Sabbath after Messiah had brought His Salvation. This event was in fulfillment of many Old Testament prophecies, for example:
6 And he said, It is a light thing that thou shouldest be my servant to raise up the tribes of Jacob, and to restore the preserved of Israel: I will also give thee for a light to the Gentiles, that thou mayest be my salvation unto the end of the earth.
7 Thus saith the Lord, the Redeemer of Israel, and his Holy One, to him whom man despiseth, to him whom the nation abhorreth, to a servant of rulers, Kings shall see and arise, princes also shall worship, because of the Lord that is faithful, and the Holy One of Israel, and he shall choose thee.
8 Thus saith the Lord, In an acceptable time have I heard thee, and in a day of salvation have I helped thee: and I will preserve thee, and give thee for a covenant of the people, to establish the earth, to cause to inherit the desolate heritages;
9 That thou mayest say to the prisoners, Go forth; to them that are in darkness, Shew yourselves. They shall feed in the ways, and their pastures shall be in all high places.
Clearly, Jesus desired His gospel to go out to all nations, including Gentiles, because both Jews and Greeks are non-existant in Christ.
11 Wherefore remember, that ye being in time past Gentiles in the flesh, who are called Uncircumcision by that which is called the Circumcision in the flesh made by hands;
12 That at that time ye were without Christ, being aliens from the commonwealth of Israel, and strangers from the covenants of promise, having no hope, and without God in the world:
13 But now in Christ Jesus ye who sometimes were far off are made nigh by the blood of Christ.
14 For he is our peace, who hath made both one, and hath broken down the middle wall of partition between us;
15 Having abolished in his flesh the enmity, even the law of commandments contained in ordinances; for to make in himself of twain one new man, so making peace;
16 And that he might reconcile both unto God in one body by the cross, having slain the enmity thereby:
17 And came and preached peace to you which were afar off, and to them that were nigh.
18 For through him we both have access by one Spirit unto the Father.
19 Now therefore ye are no more strangers and foreigners, but fellowcitizens with the saints, and of the household of God;
20 And are built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief corner stone;
21 In whom all the building fitly framed together groweth unto an holy temple in the Lord:
22 In whom ye also are builded together for an habitation of God through the Spirit.