God said to Abraham, “Kill me a son.”
Abe say, “Man you must be puttin’ me on.
God say, “No.” Abe say, “What?”
God say, “You can do what you want Abe, but
The next time you see me comin’ you’d better run.”
– Bob Dylan, “Highway 61 Revisited”
The Genesis story of Abraham being commanded by God to sacrifice his own firstborn son, Isaac,  has tied theologians from all three descendant religious traditions (Judaism, Islam and Christianity) up in knots for at least three millennia now, as they try to decipher its meaning. In his classic work, Fear and Trembling, Danish philosopher Søren Kierkegaard (1813–1855) envisioned four alternative responses by Abraham to the ethical dilemma in which God has placed him, and considered the ethical implications of each choice. It’s a tough case to reconcile. 
Kierkegaard saw Abraham’s dilemma as the key “hard case” that defines the moral rationale called “divine command” ethics. In this thread of ethical reasoning, something is right or wrong precisely because God defines it as such. So in this case, if God had personally commanded Abraham to kill his son, and God did not relent at the last moment, then the murder could not have been “wrong,” because God commanded it.
Many theologians reject this interpretation, because God did eventually relent in this story, therefore the “hard case” conveniently dissolves in this example. But this is “backfill theology,” trying to reconcile an existing reprehension of murder with the reality that, throughout history, humans have often killed “in the name of God” (and still do). The question does not go away that easily. It is at the very heart of divine command ethics, and the theology still pervades the three Abrahamic religions today in varying degrees.
In practice, divine command ethics suffers from an excess of contradictory rules presented as having divine origin. Just among Christians, for instance, you will find both practitioners of “holy war” as well as radical pacifism, each citing the divine origin of their respective beliefs, and with scriptural citations to back up each side. A second example is the role of women in the society, where committed Christians claim both divine-sanctioned subjugation of women and, on the other end of the spectrum, the divine-instituted equal worth of all persons regardless of gender. In these two of human society’s most central organizing principles, we find that “good people disagree” in ways that cannot be more opposite.
Most traditions of divine command ethics also have a heavy emphasis on what appears from the outside to be trivia, dietary laws for instance, while failing to speak out on major threats to our world’s continued survival and social justice. Some of that is to be expected, as most of these rules were written as far back as the Bronze Age. Reconciling the 21st century human and global environment with most traditions of divine command ethics is so difficult that there is a near-perfect correlation between the most ardent advocates of divine command with a strong hostility to many aspects of modern society. Modernity, including science, becomes the enemy.
Belief in an afterlife is the primary “trump card” that is often used to justify divine command ethics. If you make the wrong moral decisions in life, the threat typically goes, you will forfeit your “heavenly” afterlife, if not be condemned to the horrors of a fiery Hell.
While I cannot make the call on whether there is some larger “Divine Justice” beyond this life, I can note, in the spirit of this blog, that this is an apparent “roll of the dice.” Blaise Pascal (1623–1662) first articulated this bet, but he failed to consider all of the choices of moral arbiter on which modern humans have to wager their eternal souls. Even among Christians, you need to bet on whether your peers in Heaven include the preachers quick to condemn sinners to Hell, or instead the ones proclaiming the universal worth of human beings. If the bet has to go beyond the Christian God, then you have your pick of hundreds of often-competing theologies. Which God will show up to rule the afterlife?
Finally, proponents of divine command ethics frequently run afoul of the fuzzy line between that which is deemed immoral and that which is deemed illegal. Central to the political culture wars raging currently in the United States is the base assumption by many fundamentalist Christians that all morality arises from God, as revealed through their interpretation of the Bible (and I must note here that most Christians are not fundamentalists). For these believers, their particular “divine command” perception of morality must be the primary foundation of civil law. At the same time, they decry fundamentalist Muslims for thinking the same way about their interpretation of divine command ethics, although there is near-universal lack of understanding in America of Sharia Law and its own varying traditions.
Millions of religious believers have been able to find other models for ethical behavior (either by thinking about it or not) that better fit the reality of the world in which they live than their own particular pastor’s version of divine command. This series of posts will look at several different ways in which our society, both religious and not, and our brains have parsed the ethical dilemma.
That said, every parent likely resorts to a form of divine command ethics in child rearing at one time or another. Rather than trying to rationalize with a two-year-old child to convince the child to stay away from the hot stove, you might instead sternly command, “Get away from that hot stove! Why? Because I said so!” In much of our daily experience, we are all still ethical two-year-olds.
And here is a recent version of “Highway 61 Revisited” by Bob Dylan: