I abjure thee Satan in the name of the one true god!
Example sentence - The horrid dictator tried to abjure the faith if the people.
Has and have are two forms of the infinitive to have Has is used for he, she and it, and generally speaking third person singular. (eg Richard has a lot of friends) Have is used for all other case...
Has is used in the present: Tom has a soccer tournament today. Had is for the past: Lauren had an ice cream cone three hours ago.