Numbers 10:3

Modern

When both are sounded, the whole congregation is to assemble before you at the entrance to the Tent of Meeting.

Traditional

And when they shall blow with them, all the assembly shall assemble themselves to thee at the door of the tabernacle of the congregation.

Literal

And they shall blow both of them, and all the congregation shall gather before you at the door of the Tent of Meeting.

Latin

Cumque increpueris tubis, congregabitur ad te omnis turba ad ostium tabernaculi fœderis.

Hebrew

English

When both are sounded, the whole congregation is to assemble before you at the entrance to the Tent of Meeting.

They used the two trumpets to alert people for important announcements (compare Revelation 8–11).

Israel needed clear signals so the tribes could receive instructions. Two silver trumpets provided a simple and effective way to signal all the tribes to move.
These trumpets were not the ram’s horns (Hebrew shofar) often mentioned in the Old Testament (for example, Joshua 6:4–6). Israelite craftsmen made them from hammered silver brought out of Egypt.

Jeremiah 4:5
Announce in Judah, proclaim in Jerusalem, and say: “Blow the ram’s horn throughout the land. Cry aloud and say, ‘Assemble yourselves and let us flee to the fortified cities.’
Joel 2:15–16
Blow the ram’s horn in Zion, consecrate a fast, proclaim a sacred assembly.