https://noahideworldcenter.org/pages/preliminary-noahide-self-declaration
Before you read on, stop and answer one question to yourself, in your heart, without working to phrase it nicely: why would you not murder your neighbor?
The answer most likely came quickly. "Because it is monstrous." "Because I am not that kind of person." "Because I would not want to be murdered either." "Because a society that permits murder cannot survive." Notice your answer. Hold it for a moment. We will return to it.
The opening portion of the Torah does not begin in a mended world. Right after creating the human being, it tells of two brothers, Cain and Abel, and the first murder in history. Cain rose against his brother and killed him. One detail in this story is easy to miss: until that moment, no one told Cain, "do not murder." He was given no command. The text contains no commandment that preceded the act. And yet, immediately after the murder, the Creator turns to him: "Where is Abel your brother?"
Now return to your answer. "Because it is harmful." "Because I would not want it either." "Because such a society cannot last." These are all answers of utility, and they are correct. Truly correct. A society that permits murder indeed cannot survive, and no sane person wants to be murdered. There is no error in them.
But they have a boundary, and that boundary is precisely Cain's position. For if the only reason not to murder is utility, then the moment the calculation reverses, when the brother stands in my way, nothing remains to stop me. Cain can ask, as he asks a moment later, "Am I my brother's keeper?" And in a world of utility, that is a perfectly logical question. Why should I be his keeper?
And here is what lies hidden in "Where is Abel your brother?" It is not a question seeking information. The Creator knows where Abel is. It is a demand. It assumes an answer that the calculus of utility cannot supply: you are responsible for your brother, not because it pays, but because you are called to it.
The opposite position has a name, and the finest thinkers state it with candor. Richard Dawkins, a brilliant biologist, argues that, with time and research, we will understand everything without needing God, including morality. Most people, along this line of thought, have no wish to murder or steal in any case, and prefer a sound family life, and no Creator is needed to explain this. And we must concede that on one level he is right: reason can indeed recommend to you that you not murder. But it can only recommend. It can never demand.
Where, then, does the demand come from? The Torah itself answers, and within Parashat Bereshit. The human being is no creature like the rest: "And God created the human being in His image, in the image of God He created him." And when the prohibition of bloodshed is finally given, it is grounded not in utility but in this: "Whoever sheds the blood of man, by man shall his blood be shed, for in the image of God He made man." Not "because it is harmful," but "because in the image of God He made man." The human being carries the image of his Creator within him. One who strikes him strikes the image. The authority to demand belongs to the One who placed the image there, the Giver of life Himself. This is a demand external to the person, one the person, on his own reckoning, cannot impose on himself.
And here the depth opens. This covenant is no abstract contract in the heavens. The Creator chose to forge it with the human being precisely through the brother. "Where is Abel your brother?" means: you meet Me where you bear responsibility for your brother. Keeping the “Brotherhood Mission" is itself the meeting point with the Giver of life, because the brother carries the image. Cain asked, "Am I my brother's keeper?" and the covenant answers: yes! And precisely there, in keeping the brother, the covenant with the Creator dwells.
All of this is held in a single verse, so familiar that its depth is easy to miss: "And you shall love your neighbor as yourself, I am God." Not two separate commands: love your neighbor, and also, know that I am God. One verse: love your neighbor because I am God. See the image of God dwelling within your neighbor, and in that very seeing, you show Me your relationship to Me. The relationship to the brother is the relationship to the Creator. This is the depth of the partnership.
And one who seeks today to join himself to the Creator, in the words of the prophet Isaiah regarding "those who join themselves to God," does so through partnership with the people of God, with Israel. This partnership, a covenant between brothers on a historical scale, precisely repairs the first murderer's sin. The first brother shed his brother's blood. The one who joins forges a covenant with his brother. No covenant with the Creator without a covenant between brothers.
So we return to the question we began with, but differently. Not "why would you not murder," but: “is your morality something you arrived at by calculation, or a covenant you enter?" The two look alike from the outside. The same person, the same conduct, the same hand that is not raised. But the one floats on human reason alone, a reason that has a limit, that has shifted across history, and on which there is no agreement even today (consider, for example, the fundamentalist Islamist approach that glorifies murder "in the name of God"), while the other is held fast to its Creator like fruit to the tree.
The declaration that Noahides take upon themselves is precisely this passage. Not a surrender of the intellect, for the intellect is the crown of the human being, but a departure from a morality your reason recommended, into a covenant you sign before the Giver of life and through the brother. The question is not whether you will act rightly. The question is who you will be joined to when you do.