Translation:I am surprised that they are hugging, I thought that they are enemies.
(Avot de-Rabbi Natan, 23): ‘Who is a hero? One who turns an enemy into a friend.’
To describe something you thought (past tense), it would be more common in English to say "I thought they WERE enemies."
Does is have a common origin: אבק and להיאבק. As if fighting = dusting. :-)