“Jude, a servant of Jesus Christ, and brother of James, to those who are called, sanctified by God the Father, and preserved in Jesus Christ: Mercy, peace, and love be multiplied to you. Beloved, while I was very diligent to write to you concerning our common salvation, I found it necessary to write to you exhorting you to contend earnestly for the faith which was once for all delivered to the saints. For certain men have crept in unnoticed, who long ago were marked out for this condemnation, ungodly men, who turn the grace of our God into licentiousness and deny the only Lord God and our Lord Jesus Christ.” Jude 1-4.
“But I want to remind you, though you once knew this, that the Lord, having saved the people out of the land of Egypt, afterward destroyed those who did not believe. And the angels [fallen angels, the, “sons of God” who may have had sex with women in Genesis 6: 1-4] who did not keep their proper domain, but left their own habitation, He has reserved in everlasting chains under darkness for the judgment of the great day; as Sodom and Gomorrah, and the cities around them in a similar manner to these, having given themselves over to sexual immorality and gone after strange flesh, are set forth as an example, suffering the vengeance of eternal fire.” Jude 5-7.
Jude the last book of the Bible before Revelation was written circa 70 to 80 A.D. The author Jude, being the brother of James, thus identifies himself as being the Lord Jesus’ half brother (Judas in Mark 6:3 and Matthew 13:55), there are 4 half brothers mentioned.
“Is this not the carpenter [Jesus], the Son of Mary, and brother of James, Joses, Judas, and Simon? And are not His sisters here with us? And they were offended at Him.” Mark 6:3.