العبرة بعموم اللفظ لا بخصوص السبب

"The Lesson (and the ruling connected to it) is according to the generality of the wording not the specific reason for it's revelation."

-A general rule in Islamic Law mentioned by many scholars including Sh. Uthaymeen.

So that if there is a lesson to be learned from a Islamic text (Qur'an and Sunnah) the lesson is taken and applied generally , even if it had a specific reason for being revealed, and only becomes specific according to the specifics specified by the Islamic text connected to the text itself, regardless of the reason for its revelation.

So for example, the verse:

"And whoever among you is ill or has an ailment of the head [making shaving necessary must offer] a ransom of fasting [three days] or charity or sacrifice."-2:196

It was sent because a companion of the Prophet was facing these circumstances, making it specifically sent because of him, however, the ruling is general in that anyone who falls under the same circumstances can apply the ruling.