Following are a number of back-translations as well as a sample translation for translators of Jeremiah 6:23:

• Kupsabiny: “Those people are very arrogant/brutal
  and they carry their arrows and spears.
  They sound like a roaring ocean
  when they come on their horses
  and (they) are ready to fight against Zion!"” (Source: Kupsabiny Back Translation)
• Hiligaynon: “They are armed with arrows-and-bows and spears. They are violent and without mercy. Their noise is like the strong wave as they ride on their horses. They will-arrive ready to attack you (plur.), (who)-come-from-Jerusalem. ’” (Source: Hiligaynon Back Translation)
• English: “They have bows and arrows and spears;
  they are very cruel, and do not act mercifully to anyone.
  As they ride along on their horses,
  the horses’ feet sound like the roaring of the ocean waves;
  they are riding in battle formation
  to attack you people of Jerusalem.’” (Source: Translation for Translators)