Owl
This is a difficult riddle. The rhetorical "why?" is an indication of an unwillingness to obey. Perhaps this has the sense of that. But ya יע means 'shovel'. So the owl is the house בת of the shovel יע of the Son of Man נ, which is not understood ה.
- This suggests something like 'not understanding the death or burial of Christ'. But it is more than that. Ya יע sounds like Ya י, יא , or יה which are all names for God but uses the ayin ע which symbolizes the flesh. The shovel is an implement in the temple to move ashes from the altar.
It represents the work, in the flesh, of Christ to accomplish the purposes of the Father in his total devotion and sacrifice. With that information we can say it is something more like 'not understanding that Christ laid down his own life'. The scoffer does not understand 'Why'.