The command is "You must not kill!" What it appears to mean is that human life is not ours to dispose of in any way at all. This is true because all life belongs to God, and not to us. Hence, when we decide to murder our fellows judicially, determining that they deserve death for their actions, we in fact usurp the power of God and deny God the right to deal with that person as only God can. The command says we have no such right, however finely we sift the judicial rules, however cleverly we parse the legal language. According to this command, and its very high bar, we humans have no right to take the life of any other human being. Period! This is, of course, not to say that we do not do it, and fearfully often, but rather than gloat about it, or shout that we are doing God's work when we do it, we ought rather weep, since it is a sign that once again we have fallen short of the world that God had in mind for us.
The Ten Commandments remain worthy of our modern reflection. So, take them one at a time, give each one your most sincere attention, and this World Communion Sunday focus like a laser beam on the unity they are designed to create in a fractured world, a world without compass, a world in desperate need, though they seldom know the need, of guidelines for living in harmony and oneness with all of God's creatures. The Ten Commandments are not all we need, but they are surely some of what we need to become the community that God had in mind from the very beginning of God's creation.