With one trumpet. — Or, but once (or, at the same time). (Comp. Job 33:14; Proverbs 28:18; Jeremiah 10:8.) Some suppose that the meaning is that the trumpets were to be blown at the same time with one even or uniform sound, and that not a continuous one.
Related Commentaries of Numbers 10:4
Numbers 10:4
4 And if they blow but with one trumpet, then the princes, which are heads of the thousands of Israel, shall gather themselves unto thee.