A couple that has not been blessed with children face a great challenge. Will they wallow in their pain, and lose their faith and joie de vivre? Or will they overcome their pain, increase their love for each other, fulfill the mitzva of ona with extra joy, and constantly think about how to bring goodness and joy into the lives of their families and friends? Though they have not been blessed with children, there is great intrinsic value in their intimacy.
The Sages ask why our matriarchs were barren. One of the Sages answers, “So that they would endear themselves to their husbands through their beauty.” Another explains, “So that their husbands take pleasure in them, for when a woman is pregnant, she loses her looks and is neglected by her husband.” During the ninety years that Sarah did not give birth, Avraham treated her like a bride under the wedding canopy, and all the women inquired about her (Bereishit Rabba 45:4). Thus, from one perspective, childless couples can increase and intensify the love, passion, and joy they share.
That is the meaning behind the kabbalistic statement that each time a husband and wife unite sexually in love and passion, an abundance of life and blessing is added to this world. As Shlah states:
Each and every act of intercourse, when undertaken in sanctity, will have a positive impact. Even if the wife does not conceive…[the husband] is not wasting seed; rather, a holy soul comes into existence as a result…. For a soul comes into being with every act of intercourse, and the offspring of others are then endowed with these souls…. This is why Avraham could sleep with Sarah even though she was barren. It was not, God forbid, a waste. (Sha’ar Ha-otiyot, Kedushat Ha-zivug §402)
Shlah goes on to cite Zohar, which explains that the perfect love and devotion that infused the intimate relations of these two righteous people, Avraham and Sarah, led to the creation of souls in the supernal realms, which then descended to this world, and with which children of various families were endowed. When those children grew up, they were drawn to Avraham and Sarah, who brought them close to God. These are the souls referred to in the verse (Bereishit 12:5), “The souls they created in Ḥaran” (Zohar III 168a). Thus, when husband and wife overcome their sadness and unite with devotion and passion, they become partners in drawing down souls into the world and create sparks of souls through their sexual union.
Furthermore, when a childless couple manages, despite their pain and suffering, to strengthen their faith, deepen their love for each other, and bring one another pleasure through the mitzva of ona, they add life and blessing to the entire world. There is a special purity in their love, which is unconditional and does not depend on the children they share. Their loving unity gives expression to divine unity, revealing it in this world. Although they cannot have children, they can reveal the intrinsic value of life, thus adding vitality and continued existence to all the worlds. As Arizal explains, there are two kinds of sexual intercourse – one serves the purpose of creating souls, while the other sustains worlds and keeps them alive (Sha’ar Ha-Mitzvot, Bereishit, p. 7). It is true that even couples who have children may experience the second type of intercourse, for example when the wife is pregnant, nursing, or menopausal. However, since this is the only type of union a childless couple have, it has a greater influence on the world. All this is assuming that the love and happiness they share indeed enable them to break through the barriers of sadness and have a positive view of the world; to rejoice in the joy of relatives and friends, contribute to the world, and be kind to others as best they can.