עשה לך שתי חצוצרת כסף מקשה תעשה אתם והיו לך למקרא העדה ולמסע את המחנות
The Talmud Menachos 28b states: “All the vessels which Moshe made were valid for him and (remained) valid for future generations. (This is exclusive of) the Chatzotzros, silver trumpets, which were valid for him and invalid for future generations.” The limitations of age did not apply to such keilim, vessels, as the Menorah, Shulchan, Shofar; every utensil which Moshe Rabbeinu had made was perfectly kosher, valid, for all future generations. The silver trumpets were different. They were made by Moshe for his own use; no one else could use Moshe’s trumpets. They would have to fashion their own. The rationale…
