The question is, why would you interpret it that way? Is seeing murder helpful for your spiritual growth? That same passage could be an example of cultural norms of war. People back when drew and wrote a lot about their cultural dealings with friends and enemies. Maybe it could teach you about your personality, like the negative part of you to which god is within. Like war, it could be a struggle within yourself to do god's will (service) or follow the example of sinners to whom the spirit convicts.
Another thing about that is, would you bring everything you read in the OT in light of the 21st century. The message of justice, sin, and changing one's actions in light of those who disagree or challenge your faith is one thing, but to interpret that message as if there were a being dictating murder is something else in deed.
It really depends on the person. You'd think we gradated from B.C. but we haven't. Religion is a tool for spiritual growth; it isn't alive, and does nothing on its own.