When describing the two possessions in which the Youngs take pride—Jim's watch and Della's hair—the narrator makes an allusion to two figures from the Bible, the Queen of Sheba and King Solomon, which is also an instance of hyperbole:
"Had the Queen of Sheba lived in the flat across the airshaft, Della would have let her hair hang out the window some day to dry just to depreciate Her Majesty's jewels and gifts. Had King Solomon been the janitor, with all his treasures piled up in the basement, Jim would have pulled out his watch every time he passed, just to see him pluck at his beard from envy."
In the Hebrew Bible/Old Testament book of 1 Kings, the Queen of Sheba was said to have journeyed from an Arabian kingdom (perhaps modern-day Yemen) to bring costly gifts—such as spices, gold, and precious stones—to Israel's King Solomon. King Solomon is described in 1 Kings and other Hebrew Bible historical books as renowned for his great wisdom and unsurpassed wealth.
These allusions are obviously hyperbolic and fanciful. For one thing, these biblical figures lived thousands of years ago, in the 900s B.C.E., not in a 20th-century American city. For another, given these monarchs' tremendous wealth, they certainly wouldn't have lived or worked in cheap apartment buildings like the one the Youngs live in. To the Queen of Sheba or King Solomon, neither Della's long, beautiful hair nor Jim's heirloom watch would have warranted a second glance, much less "depreciate[d]" the Queen's treasures or provoked Solomon's envy.
The story is using humorous exaggeration to show how precious these items are to Jim and Della. The hyperbole helps underscore the point that the watch and hair are inestimably valuable, especially in the couple's drab, financially strained circumstances. By imaginatively placing these fabulously rich figures into the Youngs' poor surroundings, the allusion sets up the story's eventual twist and its lesson that true wealth doesn't consist in material possessions.