Rev 10:1 And I saw another mighty angel come down from heaven, clothed with a cloud: and a rainbow was upon his head, and his face was as it were the sun, and his feet as pillars of fire:
Rev 10:2 And he had in his hand a little book open: and he set his right foot upon the sea, and his left foot on the earth,
Rev 10:3 And cried with a loud voice, as when a lion roareth: and when he had cried, seven thunders uttered their voices.
Rev 10:4 And when the seven thunders had uttered their voices, I was about to write: and I heard a voice from heaven saying unto me, Seal up those things which the seven thunders uttered, and write them not.
2Co 12:1 It is not expedient for me doubtless to glory. I will come to visions and revelations of the Lord.
2Co 12:2 I knew a man in Christ above fourteen years ago, (whether in the body, I cannot tell; or whether out of the body, I cannot tell: God knoweth
such an one caught up to the third heaven.
2Co 12:3 And I knew such a man, (whether in the body, or out of the body, I cannot tell: God knoweth
2Co 12:4 How that he was caught up into paradise, and heard unspeakable words, which it is not lawful for a man to utter.
Paul said he knew a man that was caught up to paradise,which he is obviously talking about John.
Paul states the John heard unspeakable words,which it is not lawful for a man to utter,so there are some things John heard,that we cannot hear or say on earth,for it is not lawful for a man to utter those words.
I do not believe we can know for God would not reveal it to us if they are unspeakable words to humans,but John could hear them being in the spirit in paradise,but he could not reveal those words.
Like the Bible says that Jesus has a name that no man knows,so it would be impossible for humans to be able to figure out His name,or know it,and I believe it would be impossible for a human to be able to figure out the 7 thunders,or to know the words,for if it is unlawful for a person to utter those words,God would not reveal them,which is why the angel said,write them not.
People can try to figure,and know,but I do not believe they can,and I do not believe they can guess,for you have to already be spiritual in heaven to know.
Don't rattle your brains people,for if God does not want you to know,you will not know,and if John could not write it down,then it will not be found in any other part of the Bible,and if Paul said John heard things that are unlawful for a human on earth to utter,then we cannot speak it or even know about it.
I would not delve in to something that God said it is none of your business.