إِنْ هَٰذَا إِلَّا مَلَكٌ كَرِيمٌ
This is none other than a noble angel. (Qur'an 12:31)
“In” is negative here, equivalent to “mā”, and “illā” singles out the affirmed description. The women used this expression in astonishment at Joseph's extraordinary beauty.
Negation and exception first exclude rival possibilities and then assert one subject or quality. This Qur'anic example records their striking, figurative reaction, not a literal theological assertion that Joseph was an angel.