okay, lets talk about the word(s) translated to the English word - KILL
Lets remember first, that the Bible WAS NOT WRITTEN IN ENGLISH!
The original language in which the OT was written is that of HEBREW.
Having said that -
The Old Testament has at least 9 different Hebrew words that all convey the idea of taking a life --of killing. While all the words do carry some sort of common meaning, they also tend to each have specific emphases on the type of death: kill, beat [to death], destroy, butcher, wound [fatally], strike, sacrifice, execute, or murder.
The Hebrew word ratsách means to "murder" or "slay". While it also shares the concept of death with these other eight words, this term focuses more on the illicit taking of a life (i.e.: murder). We should be careful to distinguish this word from the other forms of killing. For example, tabách means to "butcher" (to kill for eating).
In Numbers 35:16, 17, 18, 19, and 21, ratsách is used several times, and is consistently translated as a form of "murder". The most famous use of ratsách is in Exodus 20:13, which many people know in the King James Version: "Thou shalt not kill." The KJV use of "kill" has caused some to misunderstand the verse's meaning. Any Bibles translated in the last century have removed the confusion by using the more specific "murder" for ratsách
The New Testament quotes Exodus 20:13 in Matthew 19:18, Mark 10:19, and Luke 18:20. In these verses, the Greek word used is phoneúo. Like ratsách, this word also means to "murder" or "slay". It is used for the translating of the Hebrew ratsách because they both convey the thought of taking someone's life without cause.
ratsách and phoneúo both mean to [kill by] murder (but they don't mean "beat", "destroy", "butcher", "fatally wound", "strike", "sacrifice", or "execute")
The word chosen in Exodus 20:13 is ratsách, "murder". The text does not say, "Don't take a life"; it says, "Don't kill by murder". If zabách had been used, it would have meant, "Don't kill by sacrifice". If muwth had been used, it would have meant, "Don't kill by execution", and so on.
With Hebrew having such a wide range of choices of possible words, it is important to note which word was actually selected for a specific text. It is also very helpful to note which of the words were not selected.
NOW, THIS DOES ANSWER YOUR QUESTION PERFECTLY! SO TRACK IS NOT AGAINST HIS MOTHERS RELIGIOUS BELIEFS AT ALL!
You can't limit an answer to words if you want a true answer. That is exactly why the correct translation of this word was confused.
So while the KJV may have initially said KILL, the HEBREW has always been the same and did in fact mean UNJUSTIFIED KILLING = MURDER