A few months ago our family drove to Southern California: 400 miles on Highway 5, straight down the center of the state. Now and then, we saw the mangled body of an animal hit by a speeding car.

When my children were young they reacted with anguish to any sight of roadkill. Their distaste remains today, but they have gotten used to bloodshed. As travelers look away from these carcasses on the side of the road, we who travel every year down a metaphoric Highway 5 — the Five Books of Moses — want to look away from all the animals that lie along certain stretches of the journey.

It is painful to fix our eyes on the gruesome details of animal sacrifice. The ones described so graphically in the Torah — blood and fat and bodies burning on the altar — and the ones the Torah doesn’t describe but we can’t help imagining: the mess and the stench; the cries of the animals and the look in their eyes when they’re tied up for slaughter.

Why, then, should we bother to pay attention? Can we truly study these passages as “love letters” from God — holy words that have something precious to teach us? On Shabbat, Jewish law forbids us from killing any living creature — even a fly or an ant. How, then, can it be “Shabbesdik” to immerse ourselves in the rules of ritual killing?

Generations of Jews who have journeyed through these texts have faced the same questions. Says one midrash: “The mitzvahs were given only to refine and purify human beings” (Genesis Rabbah 44:1). After all, why should a God without a body want a food offering of flesh and blood? Is God some kind of petty bureaucratic official to be bribed with gifts on the altar? No — the offering was not for God at all, says the midrash. It was for the sake of the people who brought the sacrifice.

Do you remember the film “Dead Man Walking”? The film shows that it’s hard to look closely at the clinical details of capital punishment without feeling revulsion at this calculated act of killing. So, too, Leviticus forces us to take a close-up look at the dirty mechanics of killing. It forces us to picture the spurting blood and the agony of an innocent creature put to death.

We buy our meat sanitized and shrink-wrapped in the supermarket, but Leviticus compels us to walk through the slaughterhouse. Audiences laugh and cheer the cartoonish violence in some films, but nobody laughs at the somber, harrowing death scenes in “Dead Man Walking.”

And nobody who reads Leviticus seriously, I think, can ever again be casual about the idea of taking a life.

This week’s portion begins with the words “Ki yakriv korban l’ Adonai” — “when you present a sacrifice to God.” The Sefat Emet, a Chassidic commentator, relates the words “yakriv” (offer) and “korban” (sacrifice) to the root word “karov” (close). He reads the verse as follows: “If you want to become karov — close — to God, then you must make a sacrifice.”

And what is that sacrifice? The Sefat Emet says that we have to sacrifice the animal, the beast within ourselves — the part of us that is capable of cruelty and brutality, even to those we love.

Our tradition helps us to let go of the beast within; gradually it teaches us to become sensitive human beings who cringe at the thought of giving pain to others. For instance, we are supposed to say “Shehechiyanu” when we do something for the first time, but the law forbids us to say “Shehechiyanu” when we put on new leather shoes, because an animal died to give us those shoes.

It’s a small lesson; it’s only a dumb animal, after all, who died. But our sages believed that if we think about the animal while lacing up our shoes, and refrain from saying a blessing of joy, we’ll be less likely to turn into people who drive by roadkill on the highway without giving it a thought.

The mitzvahs were given to refine our characters, to help make us menschen rather than dead men walking — insensitive beasts incapable of empathy or compassion.

And Leviticus, this blood-soaked manual of death, is for me an eternal reminder that life — all life — is sacred.

Rabbi Janet Marder is the spiritual leader at Reform Congregation Beth Am in Los Altos Hills.