A severe act of desecration takes place within the sacred grounds of the Temple when a holy storage chamber is repurposed as a private residence for an outsider. Eliashib took it upon himself to clear out and prepare a large room in the Temple complex specifically to house Tobiah the Ammonite.
To fully grasp the gravity of this act, one must understand the room's original purpose. Before this drastic change, whether this earlier period refers to the era before Nehemiah arrived in Jerusalem [רש״י] or simply the time right before the space was cleared for Tobiah [מצודת דוד], the chamber served as a dedicated storage area for distinctly holy items. It housed the fine flour meant for grain offerings and the frankincense, which were whitish grains extracted from tree resin used for offerings, the showbread, and incense. The sacred vessels of the Temple were also kept there.
Additionally, the room held the tithes of grain, wine, and oil. These agricultural gifts were part of the commandment concerning the Levites, representing the mandated portions given to the Levites, the singers, and the gatekeepers who served in the Temple. The extensive detailing of what the room used to hold is deliberate, serving to amplify Eliashib's guilt. It highlights his profound audacity in removing the rightful portions of God's servants merely to create living quarters for Tobiah the Ammonite [מצודת דוד].