How the time of the flood of Noah is used as an analogy for the last days...
Rev 12:13-17
13 And when the dragon saw that he was cast unto the earth, he persecuted the woman which brought forth the man child.
14 And to the woman were given two wings of a great eagle, that she might fly into the wilderness, into her place, where she is nourished for a time, and times, and half a time, from the face of the serpent.
15 And the serpent cast out of his mouth water as a flood after the woman, that he might cause her to be carried away of the flood.
16 And the earth helped the woman, and the earth opened her mouth, and swallowed up the flood which the dragon cast out of his mouth.
17 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.
KJV
Firstly, what comes out of one's mouth? Words, yeah that's right.
Our Lord Jesus uses the flood of Noah's time as an idea in relation to the flood of waters that come out of the dragon's mouth after the symbolic woman (God's people, including Christ's Church which has the Testimony of Jesus Christ). The serpent's flood of waters is about LIES for the end, because it's words that come out of the mouth, not a literal flood of water.
God sealed the door of Noah's ark before the waters raised it up on top of the flood waters. It was upon the height of the flood waters for 150 days, or 5 months (old Hebrew reckoning). Then the waters receded, and the ark was again upon dry ground.
That is what our Lord Jesus is using as analogy for us during the tribulation timing. The time of that flood of waters out of the serpent's mouth represents the timing of the "great tribulation". Jesus Christ is our Ark of protection through that time, so we can ride on top of Satan's lies (flood) in that time. That is how our Lord is using this idea of a flood of waters in Rev.12 about the trib.
In Isaiah 8, God used this analogy of the enemy coming up against His people like a flood of waters coming in, referring to the kings of Assyria that would take the ten tribes into captivity, and also upon Judah in the southern kingdom.
Isa 8:7-17
7 Now therefore, behold, the Lord bringeth up upon them the waters of the river, strong and many, even the king of Assyria, and all his glory: and he shall come up over all his channels, and go over all his banks:
8 And he shall pass through Judah; he shall overflow and go over, he shall reach even to the neck; and the stretching out of his wings shall fill the breadth of thy land, O Immanuel.
9 Associate yourselves, O ye people, and ye shall be broken in pieces; and give ear, all ye of far countries: gird yourselves, and ye shall be broken in pieces; gird yourselves, and ye shall be broken in pieces.
10 Take counsel together, and it shall come to nought; speak the word, and it shall not stand: for God is with us.
11 For the LORD spake thus to me with a strong hand, and instructed me that I should not walk in the way of this people, saying,
12 Say ye not, A confederacy, to all them to whom this people shall say, A confederacy; neither fear ye their fear, nor be afraid.
13 Sanctify the LORD of hosts Himself; and let Him be your fear, and let Him be your dread.
14 And He shall be for a sanctuary; but for a stone of stumbling and for a rock of offence to both the houses of Israel, for a gin and for a snare to the inhabitants of Jerusalem.
15 And many among them shall stumble, and fall, and be broken, and be snared, and be taken.
16 Bind up the testimony, seal the law among My disciples.
17 And I will wait upon the LORD, That hideth His face from the house of Jacob, and I will look for Him.
KJV
Those next Isaiah 9-17 verses actually have a latter day tribulation application. God warns of the confederacy of nations joining together to go against His people. What movement today do we see that happening with? World globalism, and the goal of a "one world government". God is saying here to not trust in it, but trust in Him instead, and wait for Him.
This is why it's important to study all of God's Word, and not just pieces of it. When you get to the idea of the waters as a flood out of the serpent's mouth in Rev.12, you should have already known about this concept of waters God used in the OT Books.