There is a mystery at the heart of Jewish existence, engraved into the first syllables of our recorded time.

The first words of God to Abraham were: “Go out from your land, your birthplace, and your father’s house . . . And I will make you a great nation . . .”

In the next chapter there is another promise: “I will make your children like the dust of the earth, so that if anyone could count the dust of the earth, so shall your offspring be counted.”

Two chapters later comes a third: “God took him outside and said, ‘Look at the heavens and count the stars – if indeed you can count them.’ Then He said to him, ‘So shall your children be.’”

Finally, the fourth: “Your name will be Abraham, for I have made you a father of many nations.”

Four escalating promises: Abraham would be the father of a great nation, as many as the dust of the earth and the stars of the sky. He would be the father not of one nation but of many. What, though, was the reality? Early in the story, we read that Abraham was “very wealthy in livestock and in silver and gold.” He had everything except one thing – a child. Then God appeared to Abraham and said, “Your reward will be very great.”

Until now, Abraham has been silent. Now, something within him breaks, and he asks: “O Lord God, what will you give me if I remain childless?” The first recorded words of Abraham to God are a plea for there to be future generations. The first Jew feared he would be the last.

Then a child is born. Sarah gives Abraham her handmaid Hagar, hoping that she will give him a child. She gives birth to a son whose name is Ishmael, meaning “God has heard.” Abraham’s prayer has been answered, or so we think. But in the next chapter, that hope is destroyed. Yes, says God, Ishmael will be blessed. He will be the father of twelve princes and a great nation. But he is not the child of Jewish destiny, and one day Abraham will have to part from him.

This pains Abraham deeply. He pleads: “If only Ishmael might live under Your blessing.” Later, when Sarah drives Ishmael away, we read that “This distressed Abraham greatly because it concerned his son.” Nonetheless, the decree remains. God insists that Abraham will have a son by Sarah. Both laugh. How can it be? They are old. Sarah is post-menopausal. Yet against possibility, the son is born. His name is Isaac, meaning “laughter”:

Sarah said, “God has brought me laughter, and everyone who hears about this will laugh with me.” And she added, “Who would have said to Abraham that Sarah would nurse children? Yet I have borne him a son in his old age.”

Finally, the story seems to have a happy ending. After all the promises and prayers, Abraham and Sarah at last have a child. Then come the words which, in all the intervening centuries, have not lost their power to shock:

After these things, God tested Abraham. He said to him, “Abraham!” “Here I am,” he replied. Then God said, “Take your son, your only son, Isaac, whom you love, and go to the region of Moriah. Sacrifice him there as a burnt offering on one of the mountains that I will show you.”

Abraham takes his son, travels for three days, climbs the mountain, prepares the wood, ties his son, takes the knife and raises his hand. Then a voice is heard from heaven: “Do not lay a hand on the boy.” The trial is over. Isaac lives.

Why all the promises and disappointments? Why the hope so often raised, so often unfulfilled? Why delay? Why Ishmael? Why the binding? Why put Abraham and Sarah through the agony of thinking that the son for whom they have waited for so long is about to die?

There are many answers in our tradition, but one transcends all others. We cherish what we wait for and what we most risk losing. Life is full of wonders. The birth of a child is a miracle. Yet, precisely because these things are natural, we take them for granted, forgetting that nature has an architect, and history an author.

Judaism is a sustained discipline in not taking life for granted. We were the people born in slavery so that we would value freedom. We were the nation always small, so that we would know that strength does not lie in numbers but in the faith that begets courage. Our ancestors walked through the valley of the shadow of death, so that we could never forget the sanctity of life.

Throughout history, Jews were called on to value children. Our entire value system is built on it. Our citadels are schools, our passion, education, and our greatest heroes, teachers. The seder service on Pesach can only begin with questions asked by a child. On the first day of the New Year, we read not about the creation of the universe but about the birth of a child – Isaac to Sarah, Samuel to Hannah. Ours is a supremely child-centred faith.

That is why, at the dawn of Jewish time, God put Abraham and Sarah through these trials – the long wait, the unmet hope, the binding itself – so that neither they nor their descendants would ever take children for granted. Every child is a miracle. Being a parent is the closest we get to God – bringing life into being through an act of love.

Today, when too many children live in poverty and illiteracy, dying for lack of medical attention because those who rule nations are focused on fighting the battles of the past rather than shaping a safe future, it is a lesson the world has not yet learned. For the sake of humanity it must, for the tragedy is vast and the hour is late.

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