There are two kinds of love.

There is love from the womb. A parent, by nature, loves a child. Siblings, from birth, are bonded to one another. The love came first; the conditions are but an afterthought.

True, the flame may burn quietly. They themselves may not even recognize their love for one another. But it burns surely, uninterrupted. It may flicker, even hide within the coals, but it is there, always.

That is why you can’t divorce your parents, or your siblings, or your own child. Because with this love you were conceived, and with it your were born. And therefore it is not in your hands to extinguish.

Then there is the love between husband and wife. It was born long after this man and woman were born. And therefore, no matter how bright the flame and intense its heat, there are conditions by which it can be torn from its wick and disappear as though it never was.

That is why the Torah tells us about marriage first within the context of divorce. The Torah does not say to us, “This is how you marry—and if you must, this is how you divorce.” Rather, it says, “If you marry, but then must divorce, this is how it shall be done.” In the Talmud, too, the tractate concerning divorce precedes the tractate concerning marriage.

Because, to keep a marriage together, you need to know that even if the flame holds tight to the wick today and leaps and crackles, tomorrow it may untie its bond and vanish. Each day anew that bond must be reinforced, and the flame must be fed, fanned and treasured.

Yes, there are times when you must run from love, when even the Torah tells you that this wick must be broken, this bond of marriage severed.

But as long as those extreme conditions have not been met, hold tight to that flame. Even if you cannot find its warmth any longer, you still hold the memory of that love. Act with love, speak with love, ponder how that love first came to be, and relive that love. Shield it through every storm, keep it burning even as the oil is but a thin film that coats the lamp’s basin. Then, surely but gradually, the flame will burn deep inside until it reaches your very soul. And there it will awaken another love, a love that never died, as permanent as that of a brother and sister, but with the fiery intensity of husband and wife.

And so Abraham told Sarah, “Say you are my sister.” So that they bonded together in an essential bond, a bonding of souls that cannot be broken.

Their souls are brother and sister—and yet closer. If they can return to that place of oneness, a new sort of love will emerge. An unconditional love.

Because, in truth, the souls of husband and wife are brother and sister—and yet closer. Before they entered this world, they were a single being. Only as they descended to invest themselves within a body did they divide. If they can persist in their journey until they return to that place of oneness, a new sort of love will emerge. An unconditional love.

What is unconditional love? It doesn’t mean that there are no boundaries, that everything is okay and nothing must be resolved. Love requires fuel; love requires a haven from wind and storm so it can burn. Unconditional love simply means that no matter what, everything can be worked out. It means that at the core we are still one, so now let us be one at the periphery as well.

As still waters mirror the face that gazes upon it, so the heart of one person mirrors the heart of the other. Show unconditional love, and eventually you will receive the same.

On the two types of love, see Likkutei Sichot, vol. 20, end of p. 40 and following, and the references listed in note 25 there.