When a person is drowning in deep pain, empty words of comfort or harsh rebuke feel exactly like tasteless, bland food. Such hollow statements are sharply rejected by the suffering soul, much like the body refuses food it cannot digest. Job responds to his friend Eliphaz by making it clear that his answers completely fail to satisfy his deep emotional hunger.
Job compares his friend's advice to food that lacks salt or is improperly prepared [רש״י, מצודת ציון]. This imagery evokes the experience of trying to eat raw meat or fish that requires heavy salting to be edible [מצודת דוד], or simply baked goods made without any salt [רמב״ן]. The primary approach among commentators is that Job is declaring his friends' words impossible to internalize, as they are completely devoid of the flavor of wisdom. Taking a different perspective, some suggest Job is actually turning the accusation around. He claims that Eliphaz listened to Job's own cries superficially, taking them in without the necessary spice and salt of deep understanding, and quickly judged him based on a shallow reading of his pain [אלשיך].
The imagery then shifts to a slimy liquid or saliva, representing something utterly devoid of flavor. Commentators offer three distinct ways to understand this tasteless substance. One approach links it to physical health, describing the natural saliva of a healthy person. While a sick person might experience a bitter aftertaste in their mouth, a healthy person's saliva has absolutely no taste at all, perfectly mirroring Eliphaz's empty arguments [מצודת דוד, רלב״ג]. A similar thought is that it refers to the watery saliva that pools in the mouth after eating something sharp and pungent like garlic [רש״י].
Another perspective connects the imagery to a raw egg. In this view, the tasteless substance is the slimy, clear egg white that surrounds the yolk [רמב״ן, רלב״ג, אבן עזרא]. This creates a powerful metaphor urging a person not to settle for the bland, external surface of a conversation, but rather to search for the inner yolk where the true flavor and profound meaning reside [אלשיך]. Finally, a third approach looks to the natural world, identifying the tasteless fluid as the slimy sap produced by a specific type of plant or vegetable [אבן עזרא, מלבי״ם, ביאור שטיינזלץ].