Following are a number of back-translations as well as a sample translation for translators of Isaiah 1:15:

• Kupsabiny: “When you raise the hands praying,
  I turn my back to you.
  Although you have prayed much to me,
  I do not listen to you at all,
  because you have spilled blood.” (Source: Kupsabiny Back Translation)
• Newari: “When you lift your hands in prayer,
  I will not look at you.
  No matter how many times you pray,
  I will not listen,
  because your hands
  are full of blood.” (Source: Newari Back Translation)
• Hiligaynon: “‘When you (plur.) pray I will- not -pay-attention to you (plur.). I will- not -listen even-though how many times you (plur.) will-pray, because you (plur.) have-killed many people.” (Source: Hiligaynon Back Translation)
• English: “So, when you lift up your hands when you pray to me,
  I will not even look at you.
  Even if you pray to me very frequently,
  I will not listen to you,
  because it is as though your hands are covered with the blood of people whom you have killed.” (Source: Translation for Translators)