Lower oneself (5)
But I've got no explanation for this one! Could you help me understand?
(Other definitions for kneel that I've seen before include "Go down on bended legs" , "Go down to be knighted" , "Show respect" , "Adopt position for prayer or submission" , "Bend one's knees" .)
'lower oneself' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for stoop that I've seen before include "Lower one's standards" , "Deign" , "Sink" , "Bent posture" , "dive" .)