Wiktionary
abjure the realm
vb. (context chiefly historical English legal English) To swear to leave the realm as soon as possible and not return without the permission of the sovereign.
Usage examples of "abjure the realm".
If I beat you, you let us all go and I promise on my word as an officer and a gentleman-and a Loring-that I'll leave England as well'abjure the realm,' to use the terminology His Majesty prefers.