ירמיהו, פרק י׳, פסוק ד׳

The process of creating an idol naturally exposes its artificiality. Because the core of the figure is carved from simple wood, its makers must coat it with precious metals to give it an impressive appearance. They apply silver and gold to beautify the object from the outside, aiming to make it visually appealing to onlookers and inspire a desire to worship it [רד״ק]. However, this decoration is completely superficial. The costly metal merely hides the plain wood beneath and has no connection to the object's actual internal essence [מלבי״ם].

To maintain this grand illusion, the expensive metal plates must be forcefully secured to the wooden body. Craftsmen use pegs and nails, driving them in with sharp, piercing hammers to attach the facade and hold the structure together [מצודת ציון].

This heavy reinforcement is required because the idol is inherently weak and prone to failure. The primary approach among commentators is that the intense nailing is necessary to prevent the valuable metal coating from breaking, peeling away, or separating from the wooden frame. Furthermore, this physical binding serves to ensure that the entire figure does not become unstable or topple over from its standing place [רד״ק, שטיינזלץ].