en_tn/jos/06/13.md

seven priests ... seven trumpets

"7 priests ... 7 trumpets" (See: rc://en/ta/man/jit/translate-numbers)

gave blasts on the trumpets

This means that they blew into their trumpets, causing them to make loud noises, multiple times. Alternate translation: "continually sounded the trumpets loudly" or "blew into the ram's horn trumpets continually"