Managing the vast wealth of the Temple required a highly organized system of dedicated officials. Among these appointed guardians were Zetham and his brother Joel, who belonged to a specific Levite family. While they are associated with Jehieli, they were actually his brothers, a relationship established in earlier genealogical records [רש״י, מצודת דוד, רד״ק].
These men were tasked with overseeing the treasuries of the House of God. Their primary responsibility was to guard and manage the silver and gold vessels used within the Temple [מצודת דוד]. The Temple courtyard housed multiple distinct treasuries, with each one dedicated to a specific purpose and need. Because managing such extensive and varied resources was a complex operation, a large team was necessary. To ensure proper oversight, each individual treasury was assigned its own specific supervisor who carried personal responsibility for its contents [רש״י, ביאור שטיינזלץ].