Rev 13:16

16 He causes all, the small and the great, the rich and the poor, and the free and the slave, to be given a mark on their right hand, or on their forehead; 

And he causes all both small and great, rich and poor, free and slave to be given a mark – the mark is the signature mark of the beast, who Daniel told us “shall intend to change time and law” (Dan 7:25). John lists the “economic groups” that will be affected by the mark. In John’s time, it was very difficult for a poor slave to rest on the Sabbath Day as God commanded, unless his master allowed it. Therefore, the commandment of God was written to masters, requiring them also to allow their servants to rest.

on the right hand or forehead – the mark against one’s forehead or right hand is a mark against the commandments of God, listed in Deut 5. In Deut 6:8, we read, “you shall bind them as a sign in your hand, and they shall be as frontlets between your eyes.” This goes back to Exod 13:9, “it shall serve to you as a sign on your forehead and a reminder on your hand that the law of the Lord may be in your mouth.” The law in this passage is in verse 6, “seven days you shall eat unleavened bread, and on the seventh day there shall be a feast to the Lord.” Here, we find the first Sabbath Day, as described in Deut 16:8, “Six days you shall eat unleavened bread, and on the seventh day there shall be a solemn assembly to the LORD your God; you shall do no work on it.” 

The mark or scratch of the beast on all men is the violation of the commandment of God to rest on the Sabbath day. This mark was enforced on all men, beginning in the fourth Century. The Catholic Church proudly boasts that moving the day of rest from Saturday to Sunday is its mark:

“Of course the Catholic Church claims that the change [Saturday Sabbath to Sunday] was her act… And the act is a mark of her ecclesiastical authority in religious things” (H.F. Thomas, Chancellor of Cardinal Gibbons).

“Sunday is our mark of authority… the church is above the Bible, and this transference of Sabbath observance is proof of that fact” (Catholic Record of London, Ontario Sept 1, 1923).

There are several clues that tell us the changing of the day of rest is “the mark”:

① Daniel said the beast would “intend to change times and law.” There is no greater representation of changing times and law (God’s law), than moving the Sabbath day from Saturday to Sunday.
② The timing given by John is the fall of the Roman Empire. The Roman Empire began its fall in the Gothic War of 376 to 381. Sunday rest was first enforced in 364 AD, by a council at Laodicea, and its enforcement continued over the next centuries.
③ Changing the Sabbath day is the only thing that would cause “all, both small and great, rich and poor, free and slave”  (Rev 13:16) to receive a mark, since the Sabbath day was made for all men, and not only for the church.
④ Satan’s attack is against those who have “the testimony” and “faith of Jesus” (Rev 12:17; Rev 14:12). The keeping of God’s commandments was considered by the Apostles to be the most significant act of a Christian (1 Cor 7:19;  1 John 3:24;  1 John 5:2-3; Acts 5:32).
⑤ If there is anything that would differentiate the Nations or Gentiles from those “who keep the commandments of God” (Rev 14:12) it is forsaking the rest of the Sabbath day.
⑥ Rev 14:11 tells that those who worship the beast, and his image and receive his mark, have “no rest day or night.”
⑦ Keeping the Sabbath Day has always been the sign of the sanctified people of God: “Speak also to the children of Israel, saying: ‘Surely My Sabbaths you shall keep, for it is a sign between Me and you throughout your generations, that you may know that I am the LORD who sanctifies you’” (Exod 31:13). Only those who keep God’s commandments can be sanctified by the holy spirit (Acts 5:32).