Following are a number of back-translations as well as a sample translation for translators of Jeremiah 15:20:

• Kupsabiny: “I will make you a wall for these people
  a strong wall of bronze.
  They may fight you
  but (they) shall not defeat you,
  because I am together with you
  to save you and guard you.
  It is me God who is speaking.” (Source: Kupsabiny Back Translation)
• Hiligaynon: “I will-make you (plur.) like a strong bronze stoned-wall to these people. They will-fight against you (sing.), but they could- not -win-over you (sing.), for I am with you (sing.), and I will-protect and save you (sing.).” (Source: Hiligaynon Back Translation)
• English: “They will fight against you,
  but I will protect you, like people are protected from their enemies by a bronze wall.
  They will not defeat you,
  because I will be with you,
  and I will protect and rescue you.” (Source: Translation for Translators)