Thus the lower creations came into being only through the lowest branch – BaN – and they therefore had to descend level by level down to there. Then man came forth to perform his service, after which, in the World of Reward, he will receive successive influences, one after the other, from all the branches that came forth for his sake – the Ears, Nose and Mouth. What will they do for him? They will elevate his plane of existence. For he exists already, but the plane of his existence will be qualitatively purer, higher and better. When all these ascents are complete, it can be said that each of the branches of Adam Kadmon will have carried out its allotted task in the repair of the lower creations that developed from them.
BaN as the Lowest Branch That Created the Lower Realms
Kalach Pitchei Chokhmah 98:10