Regarding Exodus 19, verse 16:
Why is it necessary to state that all the people “that were in the camp” had trembled?
In other words, is not the phrase “in the camp” superfluous here?
The Malbim says that Bnei Yisrael were too afraid to advance toward Hashem. They were not prepared enough to be able to hear Hashem directly, so they could not do it by themselves. Therefore, the verse stresses that they stayed in the camp; and Moses needed to bring them to Hashem himself, as it continues with "ויוצא משה את העם לקראת האלהים".
... ומזה חרדו כל העם, כי לא הוכנו לשמוע קול ה' בלא חרדה, שזה היה התנאי שיוכלו לקבל כל התורה מפי הקב"ה, אבל הם חרדו ונשארו במחנה ולא יצאו לקראת האלהים.
ויוצא משה את העם לקראת האלהים. ועי"ז הוצרך משה להוציאם בעל כרחם ע"י כחו ודבורו וזכותו...
Hebrew Scripture was structured based on the principle of dichotomy. (In simple terms, the second half of the verse modified the first half of the verse, and subsequent divisions within both halves performed the same functions, respectively.) Hebrew Scripture not only parsed verses in dichotomy, but the dichotomies were built around melody, or cantillation.
The following diagram below is one tentative, proposed reason why the phrase “that were in the camp” had to appear as the final clause of this verse for these reasons.
Please click on the image to enlarge.
Dr. William Wickes explained these observations of rules regarding cantillation in his Treatise on the Accentuation of the Twenty-One so-called Prose Books of the Old Testament. The following excerpt comes from Page 62 of his book, and provides the basis for the analysis of the diagram above.
Please click on the image to enlarge, or view the source online.