Isn't it funny how you wait for a bus... and then three come along, all on the same route, at once? And how I've never properly thought about the concept of bowing (to a being other than God)... and then have three separate discussions on the same day!
Firstly, many religious groups are extremely exuberant in their love and respect for their scholars/priests, and so bow down (to an extent) to kiss their hands.
Secondly, there's the bowing that occurs within so many Eastern martial arts; towards the teacher when entering/starting the class, towards the opponent when starting/ending a fight, and so on.
Thirdly, as found in some cultures as a mark of respect for parents.
So, does the Shariah of Islam allow this kind of bowing, given that the intention is not for idolisation? I have no idea. Any website links or suggested reading/listening would be greatly appreciated, as would your thoughts.