Jude, a servant of Jesus Christ and brother of James, To those who are called, beloved in God the Father and kept for Jesus Christ:
However, although this book takes the form of a letter, it is very carefully crafted using traditional rhetorical devices, so that Jude, in effect, writes a sermon to his friends1
1 Gardner, P. (1998). 2 Peter & Jude (p. 152). Ross-shire, Great Britain: Christian Focus Publications.