“One who has found a wife has found goodness, and has brought forth favor from Hashem” (Mishlei 18:22)
Rabbi Yudan said (Bereishit Rabbah, Toldot 65) that if there would be a halachically illegitimate male and female on opposite ends of the world, Hashem would bring them together.
A noblewoman asked Rabbi Yosi, “In how many days did Hashem create the world?”
“In six days,” was his reply.
“And with what has He occupied Himself since then?”
“He sits and arranges matches.”
To which she replied, “What’s so hard about match making? I can pair up one hundred servants with one hundred maids in one night.” And she did just that.
The next day, she called back Rabbi Yosi. She related that all night long, everyone was quarreling and hurting one another. He answered, “If making matches is light in your eyes, know that it is as difficult to Hashem as splitting the Sea of Reeds” (Yalkut Shimoni, Tehillim 247).
Rav Shmuel Bar Rav Yitzchak says that a person gets a wife according to his deeds, as the pasuk states (Tehillim 125:3), “For the rod of wickedness shall not rest upon the lot of the righteous.” Rashi explains that a modest woman is intended for the tzaddik and an immodest woman for the wicked man.
Rabba Bar Bar Chana states in the name of Rabbi Yochanan, “Finding one’s marriage partner is as difficult as splitting the sea, as the pasuk states (Tehillim 68:7), “G-d settles the solitary into a family, He releases the bound from their fetters” (Sotah 2b). When a person remains unmarried, he is considered like a force of destruction (Recanti, Bereishit 2).
Whoever remains without a wife remains without good, without joy, without blessing, without a home, without Torah, without a rampart, without peace. Rabbi Eliezer said, “Whoever does not have a wife is not considered a person. As soon as one marries, his sins disappear” (Tur, Even HaEzer, Yevamot 62b).
“G-d settles the solitary into a family, He releases those bound in fetters” (Tehillim 68:7). Just as Hashem released our nation, who were bound in fetters in Egypt, with Divine intervention, so does settling people into a family, i.e., making matches, require Divine intervention (ibid, Beit Habechirah LaMeiri).
When a person remains unmarried, it is considered “A time of evil, a sword to Hashem, full of blood” (Recanti, Bereishit 2).
The Chatam Sofer at the end of Masechet Gittin writes: The beginning of wisdom is the knowledge that man and woman share one neshamah, although they occupy two separate bodies in this world. The union between the couple is an indication of their spiritual connection on High. At first, man was created as one body with two faces, sharing one soul. After being split in two, both maintain their shared neshamah. Hashem’s Presence hovers over them as one. This is the ideal level of love. But if one of them is unfaithful, the sinful spouse becomes divorced from its source.