|What is the meaning of, "Thou shalt not kill"?|
To understand this issue -- beyond "arguments by outrage" -- requires not only a study of the Hebrew, but an element of understanding of ANE law codes as well.
To begin, the reader should be advised of a very basic fact about ancient law codes of the Near East, courtesy of Hillers' Covenant: The History of a Biblical Idea:
..(T)here is no evidence that any collection of Near Eastern laws functioned as a written code that was applied by a strict method of exegesis to individual cases. As far as we can tell, these bodies of laws served educational purposes and gave expression to what was regarded as just in typical cases, but they left considerable latitude to local courts for determining the right in individual suits. They aided local courts without controlling them.
At this point some readers might wonder if this implies that the Decalogue or the laws are something less than God's absolute word. The answer is no: But at the same time, it does indicate that these are laws that have to be read in their legal/social context.
Some laws, of course, are not open to interpretation: The commands against idolatry, for example, obviously can brook no exception, for no other God (in the modern sense; keep in mind distinction here) than Yahweh exists. But as Jesus made clear, saving a life on the Sabbath was an "exception" to the absolute prohibition of working on the Sabbath -- as was, also, priests performing certain duties on the Sabbath.
That said, can it truly be asserted that there is some discrepancy in the Biblical text on this account of killing? To answer this further and beyond mere social data we need to look at the original Hebrew words involved and figure out what they mean. Let's start with the word ratsach, from the Decalogue commandment in Exodus and Deuteronomy.
The Original Meaning of Ratsach
Our modern translations render the word "murder" rather than "kill" -- but is that really a parallel definition? It is hard to suppose that we have adequately grasped every nuance of this term, and then suppose that we can make it equal exactly some concept of Western jurisprudence.
Studies of the word by Hebrew scholars and historians are equivocal. It does seem to fit well for descriptions of what we would call manslaughter -- killing in anger. Some have suggested that it only applies to "blood revenge" killing. While scholars do disagree on some points, there are indeed certain limitations that are agreed upon one way or the other. Figuring these out comes of careful study of the text in its social and legal context.
Ratsach is used only a few times in the OT. In long passages in Numbers 35, Deut. 19, and Joshua 20-21, it is used to describe the act of someone who has committed what we might call manslaughter, or negligence; but it seems that there is more to the matter. Passing by places where the word is used but there are no contextual clues (Is. 1:21; Jer. 7:9; Hos. 4:2), we have this:
Taken together, we can discern a simple definition of ratsach: It refers to any killing that is done in the manner of a predatory animal -- which means either:
Thus we have no difficulty or contradiction in Scripture with this verse, or with places where God declares judgment of death upon men.
But there is another verse which Skeptics appeal to, Leviticus 24:17. The word here is nakah, and some make much over the fact that though this is forbidden by God, we see the Canaanites getting nakahed, David nakahing Goliath, etc.
Nakah occurs in the OT almost 500 times. But it is a word that is used in the sense of striking (Gen. 19:11, where land is nakahed), defeating or conquering (Gen. 14:5, 7, where Abraham nakahs an army). It does not mean "to kill" but is given that definition by context alone.
Being that nakah does carry this variety of nuances, it is erroneous to allege that there is some contradiction in Scripture over nakah.
In light of the above we may consider how the command "thou shalt not kill" would apply in various situations today. I will provide a few applications thought of offhand, and any reader may make or request further comment on given situations.