The shorter and longer quotes below say that the seven thunders delineate events connected with the first and second angels' messages, and thus are in the past.
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The books of Daniel and the Revelation are one. One is a prophecy, the other a revelation; one a book sealed, the other a book opened. John heard the mysteries which the thunders uttered, but he was commanded not to write them. The special light given to John which was expressed in the seven thunders was a delineation of events which would transpire under the first and second angels' messages. It was not best for the people to know these things, for their faith must necessarily be tested. In the order of God, most wonderful and advanced truths would be proclaimed. The first and second angels' messages were to be proclaimed, but no further light was to be revealed before these messages had done their specific work. This is represented by the angel standing with one foot on the sea, proclaiming with a most solemn oath that time should be no longer. {1MR 99.3}
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Daniel and Revelation. The mighty Angel who instructed John was no less a personage than Jesus Christ. Setting His right foot on the sea, and His left upon the dry land, shows the part which He is acting in the closing scenes of the great controversy with Satan. This position denotes His supreme power and authority over the whole earth. The controversy has waxed stronger and more determined from age to age, and will continue to do so, to the concluding scenes when the masterly working of the powers of darkness shall reach their height. Satan, united with evil men, will deceive the whole world and the churches who receive not the love of the truth. But the mighty Angel demands attention. He cries with a loud voice. He is to show the power and authority of His voice to those who have united with Satan to oppose the truth. {19MR 319.3}
After these seven thunders uttered their voices, the instruction comes to John as to Daniel in regard to the little book: "Seal up those things which the seven thunders uttered." These relate to future events which will be disclosed in their order. Daniel shall stand in his lot at the end of the days. John sees the little book unsealed. Then Daniel's prophecies have their proper place in the first, second, and third angels' messages to be given to the world. The unsealing of the little book was the message in relation to time. {19MR 320.1}
The books of Daniel and the Revelation are one. One is a prophecy, the other a revelation; one a book sealed, the other a book opened. John heard the mysteries which the thunders uttered, but he was commanded not to write them. {19MR 320.2}
The special light given to John which was expressed in the seven thunders was a delineation of events which would transpire under the first and second angels' messages. It was not best for the people to know these things, for their faith must necessarily be tested. In the order of God most wonderful and advanced truths would be proclaimed. The first and second angels' messages were to be proclaimed, but no further light was to be revealed before these messages had done their specific work. This is represented by the Angel standing with one foot on the sea, proclaiming with a most solemn oath that time should be no longer. {19MR 320.3}
This time, which the angel declares with a solemn oath, is not the end of this world's history, neither of probationary time, but of prophetic time, which should precede the advent of our Lord. That is, the people will not have another message upon definite time. After this period of time, reaching from 1842 to 1844, there can be no definite tracing of the prophetic time. The longest reckoning reaches to the autumn of 1844. {19MR 320.4}
The Angel's position, with one foot on the sea, the other on the land, signifies the wide extent of the proclamation of the message. It will cross the broad waters and be proclaimed in other countries, even to all the world. The comprehension of truth, the glad reception of the message, is represented in the eating of the little book. The truth in regard to the time of the advent of our Lord was a precious message to our souls. {19MR 321.1}
The greatest work to be done in this life is to make preparation for the future life, for that life which measures with the life of God. A probation has been granted us that, notwithstanding the difficulties, we may cultivate virtues which shall carry us into the higher life. Pure love for one another is exercised by those who are partakers of the divine nature. {19MR 321.2}
The whole 7 Thunders thing is quite enigmatic, as the whole Bible is the revealed will of God to man, and He saw fit to take up basically one whole chapter in his Holy Scriptures to tell us that He said something, and then told John not to write it.
What's the point?
Personally, I've met so many fanatics who are sure they've uncovered what God told John not to write, that I'm very wary of the whole subject of the 7 Thunders.
Hi Nb, a very good point, and an example of a quote that says this is the one below.
If we consider this point in connection with the original quotes I posted, it seems like there are two alternatives.
The first is that the seven thunders were unique events associated with the initial proclamation of the first and second messages, for example events peculiar to the Millerite experience.
The second is that when the three angels' messages are repeated, then the seven thunders will be repeated.as well.
I don't know which of these is correct.
It does seem like we would need to identify the specific events that made up the original seven thunders, if we're going to look for a repetition.
I don't know of much inspired material on this subject beyond the quotes I posted, and this might be a clue that making additional headway could be difficult.
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A similar work will be accomplished when that other angel, represented in Revelation 18, gives his message. The first, second, and third angels' messages will need to be repeated. The call will be given to the church, "Come out of her, My people, that ye be not partakers of her sins." "Babylon, the great, is fallen, is fallen, and is become the habitation of devils, and the hold of every foul spirit, and a cage of every unclean and hateful bird. For all nations have drunk of the wine of the wrath of her fornication, and the kings of the earth have committed fornication with her, and the merchants of the earth are waxed rich through the abundance of her delicacies. . . . Come out of her, My people, that ye be not partakers of her sins, and that ye receive not of her plagues: for her sins have reached unto heaven, and God hath remembered her iniquities" [Revelation 18:2-5]. {16MR 270.1}