The book of Enoch is non-Biblical and pseudepigraphical (what we have today is not written by Enoch). The oldest portions of the text are estimated to date from about 300 B.C.E. The book of Jude was penned by Jesus’ half-brother some 365 years later in about 65 C.E., written in Palestine.
The Book of Enoch: “Behold, he comes with ten thousands of his saints, to execute judgment upon them, and destroy the wicked, and reprove all the carnal for everything which the sinful and ungodly have done, and committed against him.”
Jude 1:14–16 Updated American Standard Version (UASV)
14 It was also about these men that Enoch, the seventh one in line from Adam, prophesied, saying, “Look, the Lord came with tens of thousands of his holy ones, 15 to execute judgment on all and to convict all the ungodly concerning all their ungodly deeds that they did in an ungodly way, and of all the harsh things that ungodly sinners have spoken against him.” 16 These men are murmurers, finding fault, following their own desires, and their mouths make excessive boasts, flattering people for their own advantage.
Some argue that Jude is quoting the Book of Enoch. Jude could have received this information from a direct revelation or by either oral or written transmission. If it was by oral or written, this would explain why similar wording to Enoch’s prophesying is found in the Book of Enoch, which dates to the second and first centuries B.C.E. There could have been a common source for both the statement in Jude and in the apocryphal book. Let us just say for the sake of argument that Jude used the statement from the Book of Enoch because he was inspired to see it was accurate information, it does not (1) make the entire Book of Enoch inspired, (2) it does not mean the statement is not the truth.
So, Jude was moved by the Holy Spirit to quote a pseudepigraphical book (“tens of thousands of his holy ones, to execute judgment on all”), or to use a source that both the Book of Enoch used and Jude. Did the Holy Spirit make a mistake? No. What we have is known as an Inspired Sensus Plenior Application (ISPA). This is a new or a progressive revelation of God, where he has inspired the New Testament writer to go beyond the intended meaning of the Old Testament writer, use a secular source that is accurate, or reference a translation instead of the Hebrew text. The New Testament authors have a license to do these things that are subjective instead of objective whereas we as interpreters cannot because they are moved along by the Holy Spirit and we are not. Jude quotes an accurate statement from the book of Enoch or a source (1:14), Paul uses allegory in reference to Hagar and Sarah (Gal. 4:21-26) Matthew at 2:15 gave Hosea’s meaning of a historical reference (11:1), giving it a sensus plenior meaning, by way of inspiration of Holy Spirit. Hosea’s meaning was a historical reference to the Israelite nation when they were in Egypt. Matthew’s meaning is to take Hosea’s words, and add new additional meaning to them, not suggesting at all that Hosea meant his new meaning. In Hebrews 11:5 Paul is using Inspired Sensus Plenior Application by referencing the Septuagint reading at Genesis 5:22 (“was pleasing to God”), to convey the meaning that God wanted to be conveyed.
On this verse, Gleason L. Archer writes,
Here we have a remarkable example of a powerful prophetic utterance coming down to us from before the time of Noah. The mere fact the Genesis does not include this statement by Enoch furnishes no evidence against his having said it. This by no means demonstrates that everything in the Book of Enoch is historically accurate or theologically valid. Much of Enoch may be quite fictional. But there is no good ground for condemning everything that is written therein as false, simply because the book is noncanonical. Even a pagan work could contain items of truth, as is attested to by Paul when he quoted Aratus’s Phaenomena 5 to his Athenian audience (Acts 17:28).
 Sinner: (hamartōlos) In the Scriptures “sinners” is generally used in a more specific way, that is, referring to those willfully living in sin, practicing sin, or have a reputation of sinning.–Matt. 9:10; Mark 2:15; Luke 5:30; 7:37-39; John 9:16; Rom. 3:7; Gal. 2:15; 1 Tim. 1:15; Heb. 7:26; Jam. 4:8; 1 Pet 4:18; Jude 1:15.
 Gleason L. Archer, New International Encyclopedia of Bible Difficulties, Zondervan’s Understand the Bible Reference Series (Grand Rapids, MI: Zondervan Publishing House, 1982), 430.
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