Revevelation 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.

Apostle John was told to seal what the 7 Thunders uttered and not to write these things. So Apostle John did seal these things and did not write them, however he gave to the Early Church a Clue where to find what the Seven Thunders had uttered:

Revelation 16:
2 And the first went, and poured out his vial upon the earth; and there fell a noisome and grievous sore upon the men which had the mark of the beast, and upon them which worshipped his image.

Read in your Bible Deuteronomy 28: 15 to 68.

Deuteronomy 28:
47 Because thou servedst not the Lord thy God with joyfulness, and with gladness of heart, for the abundance of all things;
48 Therefore shalt thou serve thine enemies which the Lord shall send against thee, in hunger, and in thirst, and in nakedness, and in want of all things: and he shall put a yoke of iron upon thy neck, until he have destroyed thee.
49 The Lord shall bring a nation against thee from far, from the end of the earth, as swift as the eagle flieth; a nation whose tongue thou shalt not understand;
50 A nation of fierce countenance, which shall not regard the person of the old, nor shew favour to the young:
51 And he shall eat the fruit of thy cattle, and the fruit of thy land, until thou be destroyed: which also shall not leave thee either corn, wine, or oil, or the increase of thy kine, or flocks of thy sheep, until he have destroyed thee.
52 And he shall besiege thee in all thy gates, until thy high and fenced walls come down, wherein thou trustedst, throughout all thy land: and he shall besiege thee in all thy gates throughout all thy land, which the Lord thy God hath given thee.
53 And thou shalt eat the fruit of thine own body, the flesh of thy sons and of thy daughters, which the Lord thy God hath given thee, in the siege, and in the straitness, wherewith thine enemies shall distress thee:
54 So that the man that is tender among you, and very delicate, his eye shall be evil toward his brother, and toward the wife of his bosom, and toward the remnant of his children which he shall leave:
55 So that he will not give to any of them of the flesh of his children whom he shall eat: because he hath nothing left him in the siege, and in the straitness, wherewith thine enemies shall distress thee in all thy gates.
56 The tender and delicate woman among you, which would not adventure to set the sole of her foot upon the ground for delicateness and tenderness, her eye shall be evil toward the husband of her bosom, and toward her son, and toward her daughter,
57 And toward her young one that cometh out from between her feet, and toward her children which she shall bear: for she shall eat them for want of all things secretly in the siege and straitness, wherewith thine enemy shall distress thee in thy gates.
58 If thou wilt not observe to do all the words of this law that are written in this book, that thou mayest fear this glorious and fearful name, The Lord Thy God;
59 Then the Lord will make thy plagues wonderful, and the plagues of thy seed, even great plagues, and of long continuance, and sore sicknesses, and of long continuance.
60 Moreover he will bring upon thee all the diseases of Egypt, which thou wast afraid of; and they shall cleave unto thee.
61 Also every sickness, and every plague, which is not written in the book of this law, them will the Lord bring upon thee, until thou be destroyed.
62 And ye shall be left few in number, whereas ye were as the stars of heaven for multitude; because thou wouldest not obey the voice of the Lord thy God.
63 And it shall come to pass, that as the Lord rejoiced over you to do you good, and to multiply you; so the Lord will rejoice over you to destroy you, and to bring you to nought; and ye shall be plucked from off the land whither thou goest to possess it.
64 And the Lord shall scatter thee among all people, from the one end of the earth even unto the other; and there thou shalt serve other gods, which neither thou nor thy fathers have known, even wood and stone.
65 And among these nations shalt thou find no ease, neither shall the sole of thy foot have rest: but the Lord shall give thee there a trembling heart, and failing of eyes, and sorrow of mind:
66 And thy life shall hang in doubt before thee; and thou shalt fear day and night, and shalt have none assurance of thy life:
67 In the morning thou shalt say, Would God it were even! and at even thou shalt say, Would God it were morning! for the fear of thine heart wherewith thou shalt fear, and for the sight of thine eyes which thou shalt see.
68 And the Lord shall bring thee into Egypt again with ships, by the way whereof I spake unto thee, Thou shalt see it no more again: and there ye shall be sold unto your enemies for bondmen and bondwomen, and no man shall buy you.