By the time the Ten Commandments were brought down Mount Sinai by Moses, the Jews already had some history with this God, whom they believed had created everything, had made covenants with Abraham and Noah, and had delivered them from slavery. By this reckoning, then, God was reality. And three millennia later, to choose something or somebody else instead of this God to guide you would be choosing something that is an illusion, says Tom McClenahan, academic dean of the Salt Lake Theological Seminary.

Just as God delivered the Jews from slavery in Egypt, he says, the Ten Commandments free people from their own misconceptions. "God released them to not just be self-centered and follow their own whims but to be a community, not just with each other but with God."

God's commandments "go further than what is convenient for you, or what is perceived in your best interests," McClenahan adds.

The Ten Commandments tell us about the nature of God, and that nature is moral — and in this way God is different from pagan deities, says the Rev. Rob Schenck. Raised a Jew and now an evangelical Christian minister, the Rev. Schenck is president of Faith and Action, an organization based in Washington, D.C., that does missionary outreach to elected officials. Its National Ten Commandments Project has given away more than 400 granite-polymer Decalogue tablets.

Without the First Commandment, says the Rev. Schenck, there is no "objective moral content ... just one religion's opinion over another's." At the time of Moses, he notes, many religions condoned human sacrifice.

While some might argue that "objective moral content" is subjective (religions differ about what constitutes modesty, for example), and would argue that morality is a human construct, based on conscience and the need to keep civilization going, Jews and Christians tend to believe that, at the very least, their God can see the bigger picture.

The human tendency to fudge, to think of things in a relative way, requires the moral authority of God, says Rabbi Benny Zippel of Chabad Lubavitch of Utah, a conservative Jewish congregation in Salt Lake City.

Here's an example of human relativism that is particularly relevant this week as people hold Holocaust remembrances, he says. "Someone like Hitler would have been a believer that murdering his fellow human beings is immoral, but when those human beings happened to be Jews, gypsies, lesbians, gays, blacks or other minorities, then not only does he consider it not immoral, he thinks it's praiseworthy" to kill.

The First Commandment, then, is a reminder: Don't take morality into your own hands. "The one who defines what is right from what is wrong is only God and nobody else other than God," Rabbi Zippel says.