Nehemiah implements a rigorous security protocol to defend Jerusalem from the hostile forces surrounding it. The strategy relies on strictly controlled access and a highly organized civilian watch. Due to the constant threat, the city's entry points are kept completely sealed throughout the night and early morning. The gates are only permitted to open once the sun is hot. The primary approach among commentators is that this refers to midday, when the sun reaches its peak heat [רש״י, מצודת דוד]. However, another perspective suggests this indicates the late morning hours [ביאור שטיינזלץ].
The daily procedure for securing the city is equally exact. While the guards are still stationed at their posts, they must physically shut and lock the doors before they are permitted to return home [רש״י, מצודת דוד, רלב״ג]. Another tradition understands this instruction as directed at the city's leaders, Hanani and Hananiah, requiring them to personally oversee the sealing of the doors [אבן עזרא]. A unique approach envisions a double-gate system: even during the hours when the massive outer gates are open, the guards must hold the smaller inner doors partially closed. This allows them to carefully monitor the flow of traffic and permit entry only to authorized individuals [מלבי״ם].
The physical act of securing the doors involves firmly grasping them to ensure they are tightly shut and reinforced with heavy bars, effectively sealing and protecting the city [רש״י, רלב״ג, אבן עזרא]. Beyond the literal locking of the gates, this directive is also understood as a metaphorical call to action. The guards are urged to hold firmly to their responsibilities, executing their duties with utmost dedication and caution without ever neglecting their posts [מצודת דוד, ביאור שטיינזלץ].
Finally, a comprehensive internal security network is established using the residents of Jerusalem themselves. The defense strategy requires a twofold commitment from the citizens. First, individuals are assigned to fixed shifts at the city entrances, primarily during the night. Second, each resident is responsible for standing watch directly in front of their own private home [רלב״ג, מצודת דוד]. To guarantee maximum efficiency and security, these guard assignments are made permanent, with strict instructions not to rotate or swap people between the different shifts [מלבי״ם].