There are two parts to this proposition: Part 1: The connection... When the male and female aspects are connected, this is perfection. Part 2: Accordingly... It is in the degree of the connection that there are differences.
Part 1: The connection of the male and female aspects constitutes perfection... This is clearly so, because male and female are the mystery of Kindness and Judgment, and the connection between them brings sweetening since Kindness sweetens the strict judgments. Moreover, the female is the receiver (מקבל, mekabel) while the male is the active influence (משפיע, mashpia). The entire function of evil is only to separate the receiver from the source of influence. From this you may infer the converse – that when male and female are joined, it is because evil is powerless to distance the receiver from the source of influence. It follows that the connection of male and female is perfection.