Following are a number of back-translations of 1 John 5:21:

• Uma: «My children, be careful that you not worship lords that are not true.» (Source: Uma Back Translation)
• Yakan: «My children-grandchildren, don’t make-into-God anything other than the true God. Wassalam» (Source: Yakan Back Translation)
• Western Bukidnon Manobo: «My children, avoid worshipping anything which is not the true God.» (Source: Western Bukidnon Manobo Back Translation)
• Kankanaey: «My children whom I love, be sure to distance-yourselves from false-gods/idols.» (Source: Kankanaey Back Translation)
• Tagbanwa: «My like children, be careful what you believe-in/obey and serve. Make sure that there is nothing at all with which you will replace this true God.» (Source: Tagbanwa Back Translation)
• Tenango Otomi: «Listen, my children, do not worship the idols which are merely manufactured.» (Source: Tenango Otomi Back Translation)
• Yatzachi Zapotec: «My little children, do not worship anything other than only God.»
• Eastern Highland Otomi: «My dear children, we must not believe the deceiving (untrue) gods. This is what we will think on now.»
• Tzotzil: «Therefore, my children, idols are not useful to us in any way (means that we should not have anything to do with them). Thus let it be.»
• Candoshi-Shapra: «Children whom I live, listen! Don’t believe in false gods. That’s all.»
• Yanesha’: «My little ones, be careful. Do not make another your Father.»
• Aguaruna: «Don’t make (for yourself) other gods little children.»
• Murui Huitoto: «Children, beware of imitations of God.» (Source for this and three above: Mildred Larson in Notes on Translation, July 1965, p. 1-15)
• Garifuna: «My children/offspring. Don’t you bow down (worship) before whatever thing that is not God.» (Source for this and three above: John Beekman in Notes on Translation 12, November 1964, p. 1ff.)