The substance of Bates’s argument to the Advent believers is this: The great book of the Revelation is the foundation of all the Adventist preaching. We have believed and preached that the message, “Fear God, and give glory to him; for the hour of his judgment is come,” met its fulfillment in the preaching of the Millerite movement. The message of the second angel, who proclaims that Babylon is fallen, and whose message is echoed by another angel in the eighteenth chapter of Revelation that declares, “Come out of her, my people,” also met its fulfillment in the Millerite movement. EGWC 186.3
Up to this point Adventists of every persuasion, unless they had turned back on the preaching of the Millerite movement, could agree. EGWC 186.4
Now, declares Bates, a third angel follows after these two; his message is a warning against receiving the mark of the beast, and those who do not receive that mark are described immediately in this language: “Here is the patience of the saints: here are they that keep the commandments of God, and the faith of Jesus.” Revelation 14:12. Why should the Advent believers give obedience simply to the first two of these three angels? There is a third message to accept—full obedience to all God’s holy commandments, including the commandment to keep the seventh-day Sabbath. EGWC 186.5
Thus did Bates and the Sabbathkeeping Adventists set forth the doctrine of the Sabbath as the third in a series of divinely indited messages intended for the closing days of earth’s history. EGWC 187.1