1. Question: Why would a person be exempt for shooting an arrow at a guy holding a shield and the shield was taken away from him right before it reaches him and he is therefore hurt or even killed but in the same scenario if the arrow just happens to properly, halachically slaughter a bird it is kosher?
A. The Gemara in Sanhedrin 77b says in the name of Rava that because there was a shield in the way when the arrow was shot which would have prevented harm then the fact it was removed before the arrow reached the victim makes it indirect killing even if the shooter himself somehow removed the shield before the arrow reached its target.
B. There is a Gemara in Chullin 30b about a case of Rava checking Rebbe Yona bar Tachlifa’s arrows to make sure they were sharp enough before being used to shoot and shecht birds in midflight.
C. The Gemara in Chullin 15b-16a says that one who shechts using a knife powered by a water mill is not kosher because it is not your direct power, rather it is secondary power of your which is causing the slaughter to happen and therefore it is indirect and invalid.
D. By hurting or killing someone the sin is the act of killing or damaging.
E. The mitzvah of shechita does not need an act of shechita but that shechita comes from his power.
Answer: By the murder or injury we can say that it wasn’t his action of shooting that killed or hurt the person since the shield was in the way when the arrow was shot but by the slaughter, though the shechita would not have happened when the shield was there but it was taken away and it was because of the power of his shot that it was shechted properly therefore it is kosher.