On various occasions I have had some conversations with others on the idea of the commandment of "Thou Shall Not Kill", this is used as an attempt to justify some contradictions within the Bible. Or even the idea that Christians should not end life at all, or be involved in wars.
The trick is, the bible never says "Do not kill. In fact, what it actually says is "Do not murder". Could there really be a difference? Yes.
Now there is a longer discussion we could get into on that, but let's save that for another time. This article I would like to share what makes murder different from killing.
According to Bakers Bible Dictionary
Murder is distinguishable in the Bible from the larger category of killing. Thus, the sixth commandment (Exodus 20:13) is appropriately translated by the NIV and other versions as "You shall not murder" rather than "You shall not kill." The taking of lives in warfare, for example, would not have been considered murder. The word used in Exodus 20:13, ratsakh, occurs approximately 50 times in the OT and never refers to killing in battle, in contrast to two other words for kill that together occur over 300 times and quite often refers to battle contexts. Ezekiel 21:22 (21:27 MT) might appear to be an exception, but ratsakh (NIV: slaughter) is probably used there to indicate the slaying of innocent people rather than military combatants.
Ratsakh, however, can also refer to unintentional killing or manslaughter (e.g. Numbers 35:11); thus, the word does not necessarily mean murder but rather refers to taking an innocent life, whether intentionally or accidentally. The lone exception in Numbers 35:30. is only apparently so; it is rather a statement of poetic justice; "The murderer shall be murdered".
The prohibition against murder is grounded in the image-bearing character of humankind. Human beings are made in the image of God; therefore, to kill an innocent person is equivalent to striking out against God (Genesis 9:6)
Significantly, Jesus viewed His own approaching death in Jerusalem as murder in a long line of murders stretching from the murder of Abel by Cain, through the killing of the OT prophets, to Himself (Matt. 21:33-46; 23:29-39; Luke 11:47-54; 20:9-20)