# The vision of Obadiah

This is the title of the book. Here "vision" is used in the general sense of a message from Yahweh, rather than to indicate how Obadiah received the message. Alternate translation: "The message of Obadiah" or "The prophesy of Obadiah"

# The Lord Yahweh says this concerning Edom

This tells the reader that the entire book is a message about Edom

# Yahweh

This is the name of God that he revealed to his people in the Old Testament.

# an ambassador has been sent

"Yahweh has sent an ambassador" 

# Rise up

"Stand up." This phrase is used to tell people to get ready.

# rise up against her

Here "her" refers to Edom. It could also be translated as "them."