Okay.
Who had the authority to define sin? Did God have that authority? I would say yes. Did Jesus have that authority? I would say yes.
Is there anybody other than God or Jesus who had, or has, the authority to define sin? Put another way, is there anyone other than God or Jesus who had the authority to issue commandments?
And your point for me is...?
Let me walk you through a scenario for a guy at this point and try to describe a scene out of the page of life.
Let's say you (this man) considers he has a real squirrel tree rat problem exasperated by a neighbor a few doors up by them having not one but two squirrel feeders. And say over a 3 year period the number of varmints have multiplied by 10-fold. And because of their ignorance and or selfishness of this neighbor, this current year these swarming varmints have now eaten all kinds of green matter and flowers and have gotten into attics and chewed up wires and the wires in vehicles etc. costs hundreds and even thousands of dollars worth of property damage.
This man now says enough is enough and wants to fix the problem...
So then a neighbor a few doors away wants to do something within the law and quietly. He is seasoned hunter. He has an air rifle with a great scope and knows how to use it. He is careful with his aim and environment always and only shoots from his back door only. Over several months he kills dozens of these tree rats and the problem is now controlled.
Now this person is a Christian as he says. Does God condemn him and say he has sinned. I know lots of people would say he is a murderer.
What say ye...did he sin? And to add, this man is not convicted of sin in the least, and he used to go hunting all the time for food and varmint control when he was younger.