Aliya Summary: From the day the Tabernacle was erected, it was covered by a cloud during the day, and a fire by night. When the cloud lifted, this signaled G‑d’s wish that the Jews should journey onwards — following the cloud until it came to rest in a new location of G‑d’s choosing. In some cases the Jews only stayed overnight in a particular location before the sign came for them to depart again, and on other occasions they would stay in one place for many years. This Aliya then discusses Moshe’s two silver trumpets. These trumpets were used for several purposes: 1) To assemble the nation or its leaders. 2) To signal the beginning of a journey. 3) The trumpets were blown when the Jews went to battle. 4) The trumpets were sounded when certain communal sacrifices were offered in the Tabernacle.
The above-mentioned purposes of the trumpets applied to the generation of the wilderness only, but the mitzva for future generations concerning the trumpets is as follows: When the People enter the Land of Israel, the trumpets are to be used during times of troubles and on festive occasions during Temple service.