The biblical book after Micah is Nahum, which is five letters long. Nahum is a book of the Hebrew Bible, also known as the Old Testament. It is part of the Minor Prophets, and is believed to have been written by the prophet Nahum around the 7th century BC. The book contains prophecies of the destruction of Nineveh, the capital of Assyria, and is seen as a warning to those who do not follow God's laws.