Does the Prophet's (peace be upon him) silence regarding a one-time act constitute an affirmation that necessitates acting upon it, and does the lack of repetition of the act or explicit mention of it later mean that it is not recommended or not a Sunnah?

The mere silence of the Prophet (PBUH) regarding an action does not indicate its desirability or sunnah status; rather, it only indicates its permissibility. This permissibility signifies allowance and the removal of prohibition, not sunnah or obligation.

Al-Shatibi explained that approval of a rare, non-worshipful act, outside of common practice, where the approval does not imply generalization or emulation, does not indicate its legitimacy, neither initially nor continuously. An example is the story of Abu Lubabah when he tied himself to a pillar in the mosque. His action was not with the Prophet’s (PBUH) permission, and the Prophet (PBUH) left him until Allah judged concerning him. This was a specific matter for the time of revelation, and it is not permissible to emulate it.

There is disagreement regarding the story of Abu Lubabah. It was said that it occurred concerning Banu Qurayza, and it was also said that it was during the Tabuk expedition, where he tied himself to a pillar and abstained from food and drink until he fainted, then Allah accepted his repentance. Al-Dehlawi pointed out that Abu Lubabah's action was a state of overwhelming emotional compulsion, not a legislative intention.