Passing fair

An archaic meaning of passing is surpassingly. Thus, although the flowers are surpassingly beautiful, Angelina is even more so (181, 263, 274). Brewer (56) opines that the expression comes from the Dutch word passen, to admire. See entry for “Passing” in Ruddigore.

Context: 
Though thy beauty rare shame the blushing roses ––They are passing fair!
Act: 
Act