The Book of Jude is a short letter in the New Testament of the Christian Bible. Traditionally attributed to Jude, a brother of James and possibly a brother of Jesus, it addresses early Christians and warns them about false teachers and immoral behavior. Jude emphasizes the importance of faith and encourages believers to remain steadfast in their beliefs. The letter also references historical examples, such as the rebellion of Korah and the destruction of Sodom and Gomorrah, to illustrate the consequences of turning away from God.