from my understanding
The first test is Revelation’s 18:1-2

“.. We are not to give the message in so indifferent a manner. The message of (Revelation 18:1, 2) contains the great test for the people. It is to be given with a solemn sense of its importance, that it may do its special work.. 22LtMs, Lt 296, 1907, par. 4”

Revelation 18:1-3 is connected with some great buildings coming down in New York by the power of God .

“Now comes the word that I have declared that New York is to be swept away by a tidal wave. This I have never said. I have said, as I looked at the great buildings going up there, story after story, “What terrible scenes will take place when the Lord shall arise to shake terribly the earth. Then the words of (Revelation 18:1-3) will be fulfilled. The whole of the eighteenth chapter of Revelation is a warning of what is coming on the earth.. 18LtMs, Lt 176, 1903, par. 10-18LtMs, Lt 176, 1903, par. 11”

The 2nd Test : the Imagine of the beast – Church and State uniting with the church in control

“..The Lord has shown me clearly that the image of the beast will be formed before probation closes; for it is to be the great test for the people of God, by which their eternal destiny will be decided. Your position is such a jumble of inconsistencies that but few will be deceived. . 6LtMs, Lt 11, 1890, par. 10”

The 3rd Test: – the 7th day Sabbath

“In (Revelation 13) this subject is plainly presented: “I beheld another beast coming up out of the earth; and he had two horns like a lamb, and he spoke as a dragon. And he exerciseth all the power of the first beast before him, and causeth the earth and them that dwell therein to worship the first beast, whose deadly wound was healed.” [Verse 11.] Then the miracle-working power is revealed: “And deceiveth them that dwell on the earth by the means of those miracles which he had power to do in the sight of the beast; saying to them that dwell on the earth, that they should make an image to the beast, which had the wound by a sword, and did live. 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. And he causeth all, both small and great, rich and poor, free and bond, to receive a mark in their right hand, or in their foreheads, and that no man might buy or sell, save he that had the mark, or the name of the beast, or the number of his name.” [Verses 14-17.]
This is the test that the people of God must have before they are sealed. All who prove their loyalty to God by observing His law, and refusing to accept a spurious Sabbath, will rank under the banner of the Lord God Jehovah, and will receive the seal of the living God. Those who yield the truth of heavenly origin, and accept the Sunday Sabbath, will receive the mark of the beast. What need will there be of the solemn warning not to receive the mark of the beast, when all the saints of God are sealed and ticketed for the New Jerusalem? “O consistency, thou art a jewel!” . 6LtMs, Lt 11, 1890, par. 11-6LtMs, Lt 11, 1890, par. 12