False teachers had come into the church. Jude wrote in order to encourage Christians to fight for the faith once for all revealed to God's people. Jude teaches us that we must oppose error, even within the Lord's church. The book of Revelation is a book of prophecy. It was written by John.
Revelation is written in symbolic language.
Most of Revelation should not be interpreted as it is stated. A person must understand what the symbols mean. Only then can he interpret it properly. Also, many of the things mentioned have already happened. Please include the teacher information as you complete each lesson.