The Remnant of God
In the last days there will be two groups.
1. Those who worship God (keep the commandments), and have the Seal of God.
And the dragon was wroth with the woman, and went to make war with the remnant of her seed, which keep the commandments of God, and have the testimony of Jesus Christ.
- Revelation 12:9 (KJV)
Nevertheless the foundation of God standeth sure, having this seal, The Lord knoweth them that are his. And, let every one that nameth the name of Christ depart from iniquity.
- 2 Timothy 2:19 (KJV)
2. Those that worship satan, and have the mark of the beast.
And the third angel followed them, saying with a loud voice, If any man worship the beast and his image, and receive his mark in his forehead, or in his hand.
- Revelation 14:9 (KJV)
The main difference between these two groups is in the day that they worship.
The remnant keeps the sabbath commandment (part of the Ten Commandments).
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.
- Isaiah 66:23 (KJV)
But satan will try and force you to worship him on his day (Sunday).
Of course the Catholic Church claims that the change [from Sabbath to Sunday] was her act. And the act is the mark of her ecclesiastical power and authority in religious matters.
- Faith of Our Fathers, p. 14 C.F. Thomas, Chancellor of Cardinal Gibbons
And he had power to give life unto the image of the beast, that the image of the beast should both speak, and cause that as many as would not worship the image of the beast should be killed.
- Revelation 13:15 (KJV)
In the last days you will need to make a decision (in your forehead) to what group you belong.
You either keep the commandments of God (including the sabbath), or you will receive the mark of the beast.
The mark of the beast = knowingly keeping Sunday instead of Sabbath.