The Reverend (Rev.) is a style most often used as a prefix to the names of Christian clergy and ministers. There are sometimes differences in the way the style is used in different countries and church traditions. The Reverend is correctly called a style but is often and in some dictionaries called a title, form of address or title of respect. The style is also sometimes used by leaders in non-Christian religions such as Judaism and Buddhism.
The Reverend is therefore equivalent to The Honourable or The Venerable.