In the sixth chapter of the Book of Revelation, Jesus Christ opens a scroll which is sealed with seven seals. When opened, six of the seals release specific types of judgment onto the earth.
Then I saw in the right hand of him who sat on the throne a scroll with writing on both sides and sealed with seven seals. 2 And I saw a mighty angel proclaiming in a loud voice, “Who is worthy to break the seals and open the scroll?” 3 But no one in heaven or on earth or under the earth could open the scroll or even look inside it. 4 I wept and wept because no one was found who was worthy to open the scroll or look inside. 5 Then one of the elders said to me, “Do not weep! See, the Lion of the tribe of Judah, the Root of David, has triumphed. He is able to open the scroll and its seven seals.”
Revelation 5:1-5 NIV
The First Five Seals
The first five seals are conquest, war, famine, death and martyrdom. Could these five seals have already been fulfilled? The amount of human misery caused by these five occurrences during the past two thousand years has been more than adequate to have fulfilled the first five seals. Any student of history would have to agree that there has been so much conquest, war, famine, death and martyrdom on the earth during the last two thousand years, that you don’t need to have any more added, in order to justify an argument that the first five seals may already have been fulfilled.
The Sixth Seal
12 I watched as he opened the sixth seal. There was a great earthquake. The sun turned black like sackcloth made of goat hair, the whole moon turned blood red, 13 and the stars in the sky fell to earth, as figs drop from a fig tree when shaken by a strong wind. 14 The heavens receded like a scroll being rolled up, and every mountain and island was removed from its place.
15 Then the kings of the earth, the princes, the generals, the rich, the mighty, and everyone else, both slave and free, hid in caves and among the rocks of the mountains. 16 They called to the mountains and the rocks, “Fall on us and hide us[f] from the face of him who sits on the throne and from the wrath of the Lamb! 17 For the great day of their[g] wrath has come, and who can withstand it?”
Revelation 6:12-17 NIV
The 2004 Indian Ocean earthquake and tsunami and the Nias-Simeulue earthquake
Revelation 6:12-17 seems to be describing a tsunami because of three things:
There was a great earthquake (Rev 8:12). A great undersea earthquake caused the tsunami.
The heavens receded like a scroll being rolled up. A tsunami affects the atmosphere above it, causing waves in the atmosphere, which could be described as the heavens receding like a scroll being rolled up:
https://visibleearth.nasa.gov/images/77377/quake-and-tsunami-makes-waves-in-the-atmosphere
https://www.livescience.com/8782-tsunamis-send-mysterious-waves-earth-atmosphere.html
Also, mountains and islands were removed from their place because the entire earth wobbled on its axis as a result of the tsunami and islands were moved:
https://www.theage.com.au/national/tsunami-quake-wobbled-earths-axis-20041228-gdz9ru.html
https://www.latimes.com/archives/la-xpm-2004-dec-27-sci-tsunami27-story.html
According to Wikipedia’s article about the tsunami:
Early speculation was that some of the smaller islands south-west of Sumatra, which is on the Burma Plate (the southern regions are on the Sunda Plate), might have moved south-west by up to 36 m (120 ft), but more accurate data released more than a month after the earthquake found the movement to be about 0.2 m (8 in).[37] Since movement was vertical as well as lateral, some coastal areas may have been moved to below sea level. The Andaman and Nicobar Islands appear to have shifted south-west by around 1.25 m (4 ft 1 in) and to have sunk by 1 m (3 ft 3 in).[38]
https://en.wikipedia.org/wiki/2004_Indian_Ocean_earthquake_and_tsunami
The Jewish tsunami victims
The sun turned black like sackcloth made of goat hair, the whole moon turned blood red, 13 and the stars in the sky fell to earth, as figs drop from a fig tree when shaken by a strong wind.
Revelation 6:12b-13
The sun, moon and stars symbolize Israel in the Bible. In Genesis 37 Joseph has two dreams, the second of which depicted his family as the sun, moon and stars:
9 Then he had another dream, and he told it to his brothers. “Listen,” he said, “I had another dream, and this time the sun and moon and eleven stars were bowing down to me.”
10 When he told his father as well as his brothers, his father rebuked him and said, “What is this dream you had? Will your mother and I and your brothers actually come and bow down to the ground before you?” 11 His brothers were jealous of him, but his father kept the matter in mind.
https://www.biblegateway.com/passage/?search=Genesis%2037%3A9-11&version=NIV
In Revelation 12:1-6 the nation of Israel is symbolically referred to as a woman clothed with the sun and moon and wearing a crown of stars.
Therefore, it is possible that the reference to the sun, moon and stars in Revelation 6:12-13 could be a reference to the Jewish people who were killed by the 2004 tsunami. There were a number of Jewish people who lost their lives in the tsunami. The following articles speak about some of those Jewish victims:
https://www.jweekly.com/2005/01/14/jewish-couple-embarking-on-new-life-killed-in-tsunami/
https://www.sajbd.org/media/the-2004-tsunami-and-south-african-jewry
https://www.jta.org/archive/israel-jewish-groups-pitch-in-to-help-victims-of-quake-tsunami
https://www.ourjerusalem.com/news20041231/
A comparison of Matthew 24:29 and Revelation 6:12
“Immediately after the distress of those days
“‘the sun will be darkened,
Matthew 24:29 NIV
and the moon will not give its light;
the stars will fall from the sky.
The sun turned black like sackcloth made of goat hair, the whole moon turned blood red, and the stars in the sky fell to earth, as figs drop from a fig tree when shaken by a strong wind.
Revelation 6:12 NIV
We see that this is a description of the same events, but using slightly different wording. Therefore, it is possible that the tsunami in 2004 heralded the return of Jesus.
We can say that Jesus is coming back in this century because he said that the generation who saw these things, the sun being darkened and the moon not giving its light and the stars falling from the sky, would not be dead before He came back:
32 “Now learn this lesson from the fig tree: As soon as its twigs get tender and its leaves come out, you know that summer is near. 33 Even so, when you see all these things, you know that it[e] is near, right at the door. 34 Truly I tell you, this generation will certainly not pass away until all these things have happened. 35 Heaven and earth will pass away, but my words will never pass away.
Matthew 24:32-35 NIV
He must have been saying that the generation that witnessed the 2004 tsunami, would not die until before his return.
Evacuation to the mountains
Then the kings of the earth, the princes, the generals, the rich, the mighty, and everyone else, both slave and free, hid in caves and among the rocks of the mountains.
Revelation 6:15
While I could find no accounts on-line regarding people hiding in caves and among the rocks of the mountains on the 26th December 2004, when the initial tsunami event occurred, I did find an account of how people fled into the mountains and hid during the aftershock, which occurred on March 28, 2005. This aftershock, called the Nias-Simeulue earthquake, was also a very powerful earthquake:
According to a BBC news article, this aftershock caused mass panic and people evacuated into the mountains:
Local residents said Wednesday’s earthquake, which hit Simeulue at 1508 (0808 GMT) according to the United States Geological Survey (USGS), lasted for almost a minute.
It was felt strongly more than 300km (185 miles) away in the provincial capital, Banda Aceh, where people left their offices after buildings started shaking.
“Everything shook very strongly for more than a minute and I ran along with the others. I heard people screaming in panic,” Ahmad Yushadi told the Associated Press news agency.
An official from the Indonesian ministry of health, Rustam Pakaya, said the authorities on Simeulue had reported three deaths and 25 serious injuries caused by the earthquake.
“People have evacuated to the mountains,” he said.
http://news.bbc.co.uk/1/hi/in_depth/7254325.stm
Fear of judgment
16 They called to the mountains and the rocks, “Fall on us and hide us[f] from the face of him who sits on the throne and from the wrath of the Lamb! 17 For the great day of their[g] wrath has come, and who can withstand it?”
Revelation 6\;16
Prior to the tsunami, there had been considerable persecution of the Christians in Indonesia. At Christmas in 2000, churches were bombed:
http://news.bbc.co.uk/1/hi/world/asia-pacific/1086275.stm
In January 2004 churches were attacked:
https://www.worthynews.com/353-protestant-churches-sustain-attacks
In September 2004 twelve churches were ordered to close:
https://matt510.wordpress.com/2004/09/
https://christianpersecution.info/indonesia-closes-12-churches-in-bandung/
In November 2004 a pastor was murdered and on 14 December 2004 two more churches were attacked:
https://matt510.wordpress.com/2004/12/
Given the level of persecution that Christians were experiencing prior to the tsunami, it is justifiable to believe that the people fleeing into the mountains may have interpreted the tsunami as an act of retaliation on the part of the Christian God. This is why they would have been calling to the mountains and the rocks, “Fall on us and hide us from the face of him who sits on the throne and from the wrath of the Lamb! For the great day of their wrath has come, and who can withstand it?”