It is not in the Bible, even though there is a reference to it in Jude verses 14 and 15: "Now Enoch, the seventh from Adam, prophesied about these men also, saying, 'Behold, the Lord comes with ten thousands of His saints, "to execute judgment on all, to convict all who are ungodly among them of all their ungodly deeds which they have committed in an ungodly way, and of all the harsh things which ungodly sinners have spoken against Him."'
The Bible does not explain where Jude found this prophecy and the simplest and most plausible explanation is that the Holy Spirit transmitted to him all the text of the epistle, also including these verses.
Enoch was a very special and remarkable man, for he walked with God, and at the end of his 365 years of life (the number of days in one year) "he was not, for God took him". (Genesis 5:24): justified by faith Enoch was taken away so that he did not see death (Hebrews 11:5).
By means of a revelation by God, for he walked with Him, Enoch prophesied the coming of the LORD with His saints for the judgment of all. A long time after his rapture came the Flood that destroyed all humanity except for the family of Noah, but evidently this was not the judgment foreseen by him. This was the first prophecy concerning the coming of the Lord Jesus Christ in glory with His saints to judge the world, confirmed later on in the Old Testament (e.g.. Zechariah 14:5), and announced by Christ and His apostles.
Just as Enoch was removed from this planet without passing through death, also the believers in Christ, who will be alive at the time of the Rapture of the Church, will be translated and will be among His saints to come back and to judge the world. This was only disclosed after the times of the Old Testament, however Enoch can be seen as a type or representative of these believers. They will be withdrawn from earth before the judgment of the great tribulation, as Enoch was before the flood. Some researchers, not satisfied with the simple inspiration of the Holy Spirit for this revelation through Jude, have been looking for some reference in other literature not included in the Bible, existing in the time of the apostles.
In 1773 one of them found a " Book of Enoch " inside an Ethiopian Bible. One of the writers of the second century AC had referred to this book, but it was lost through time with the exception of a few fragments. The passage is inside this book, which had been rejected by the Godly men in its time and was excluded from the Bible for being "apocryphal", or invented, without authenticity. It is not known accurately when it was written, there is no evidence that it was before Jude, and it is even probable that the prophecy found in Jude was placed in the book to make it seem authentic.
The Greek word Apocrypha (meaning hidden or private) is generally used in general for a collection of books, the number of which goes from eleven to sixteen, which appeared between the Old and the New Testaments. They have more or less connection with canonic books (found in our Bibles), and their history has been a matter of controversy.
The opinion of theologians on the value of these books has always varied a lot. The Jewish theologians who dispersed into Egypt two centuries before Christ had a high regard for these books, and they even included them in their Greek translation of the Old Testament, known As the " Septuagint ". The theologians of Palestine rejected them and never included them in the Hebrew canon from which our Bibles are translated.
The apocryphal books are called Ezra (2), Tobit, Judith, Additions the Esther, the Wisdom of Solomon, Ecclesiasticus, Baruch, the Letter of Jeremiah, Song of the Three Holy Children, Susanna, Bel and the Dragon, the Prayer of Manasseh and Maccabees (2).
Authorities differ as to the classification of these books. The Roman Catholic Institution, in the Council of Trent of year AD 1546, declared eleven of these books to be canonical and these appear in modern editions of its Bibles.
Although these books contain material of literary and historical value, their legitimacy as part of the Word of God inspired by the Holy Spirit is rejected by the theologians not tied to this institution, and they do not appear in our Bibles because:
They were never mentioned by the Lord Jesus, and it is very doubtful if they were ever alluded to by the apostles.
Most of the scholars of the first centuries of the Christian age considered them uninspired.
They did not appear in the old Hebrew canon.
The inferior quality of the majority of the texts, as compared with the canonic books, evidences that they are unworthy of being included in the Holy Scriptures. the ones that evidently have the divine inspiration.
The Lord Jesus declared the span of the canonic books of the Old Testament when he accused the scribes of being guilty of the murders of all the prophets sent by God, from Abel to Zechariah (Luke 11:51). The death of Abel is recorded in Genesis; the death of Zechariah is found in 2 Chronicles 24:20-21, and that is a portion of the last book of the Hebrew Bible (instead of Malachi, as in our Bibles). Our Master was declaring that the guilt of the Jews was recorded from the start to the end of the Hebrew Holy Writs. It excluded all the apocryphal books, which already existed at that time, and had been written after those.
Curiously, the apocryphal books do not pass in the "test of the seven", created by Dr. Ivan Panin, a linguist and Jewish mathematician, who in 1900 discovered that by substituting each letter in the Hebrew text of the Old Testament for its numerical equivalent, a surprising repetition of number 7 and its multiples is found, in many forms.
The probability of only 12 of the many forms found to appear together in a writing of moderate size is of one in many millions, therefore there is no possibility of this having happened simply by chance.
When testing the old Greek of the New Testament, the same characteristics were found. Upon discovering this, Dr. Panin, who had been an agnostic, believed in the Gospel and became an ardent evangelist.
It seems clear that the Roman Catholic Institution tries to give legitimacy to these books, grafting them in its Bible, because in them there is a rare reference to prayers for the deceased in order to exempt them from punishment in hell. It would be a justification for the purgatory that it invented.
The Bible, as we have it now, is complete. There is no place or justification for grafts. Unfortunately, under the excuse of making the Bible easier to read and to understand, there are modern "popular language" versions that graft inexistent words, as well as specially prepared versions which distort the Biblical text to dissimulate the obvious heresies that its publishers want to spread.
In our studies, let us be careful with the translation that we use, to be able to correctly interpret the teaching that the Holy Spirit is giving us. Fortunately we have available already good commentaries written by men of God who have a deep knowledge of the texts in their original languages and they are of great value in obtaining clarification of some more obscure and rare expressions, of difficult understanding.