* Shall: This word has roots in Old English, where it was used to express obligation or determination. It eventually evolved into a modal verb, indicating future tense or a strong sense of volition.
* Not: This word is derived from the Old English word "nā," meaning "no."
Therefore, the phrase "shall not" came about through the natural development of English grammar, combining the modal verb "shall" with the negation "not" to express prohibition, obligation, or a strong negative statement.
While there isn't a single specific historical moment that marks the origin of "shall not," it's important to note that the use of modal verbs like "shall" and their combination with negations like "not" is a feature of many languages, highlighting the universality of these grammatical structures.
It's also worth noting that the use of "shall not" has changed over time. While it was once used in formal contexts to express obligation or prohibition, it has become less common in everyday speech. It's still used in legal documents and other formal settings, but in casual conversation, "will not" is often preferred.