Following are a number of back-translations as well as a sample translation for translators of Jeremiah 30:21:

• Kupsabiny: “A person from their own community shall rule over them,
  one from their house/family shall lead (them).
  I will draw that leader to come near to me,
  because who is the one who will devote himself to be near me?” (Source: Kupsabiny Back Translation)
• Hiligaynon: “Their leader will-be from their very own. I will-cause- him -to- come-near to me, and he will-come-near-(to-me). For there is no man who will-dare to come-near to me if I will- not -cause- him -to-come-near (me). I, the LORD, is saying that” (Source: Hiligaynon Back Translation)
• English: “One of their own people will be their king,
  and I will invite him to come close to me to worship me,
  because no one would dare/have courage to come close to me
  if I did not invite him.” (Source: Translation for Translators)