Those who find fault shall receive instruction.
Ironically, one can find fault with this translation, for the expression translated here as “find fault” is more commonly and more safely translated as “murmur”.
To be sure, as our Lord says (Matthew 7:1), we should not judge, lest we be judged. We need to help each other overcome our faults and grow in holiness as much as we can, but ultimately only the Lord knows perfectly, judges perfectly, and gives instruction perfectly.
(Lord Jesus Christ, Son of the living God, be merciful to me – a sinner.)
Those who murmur will accept instruction.
There may be much in our lives about which we might be able to murmur, find fault, complain, or grumble, but in these things and in all things the most important and necessary activity is for us to learn: to learn the plan, the purpose, and the path of God.