The apostle Peter was inspired to quote this part of Psalm 34 after he counseled Christians to treat one another with brotherly affection. Safeguarding our tongue from what is bad means that we will avoid spreading harmful gossip.
وَلكِنْ شَتَّانَ مَا بَيْنَ ٱلْقَوْلِ إِنَّنَا نُحِبُّ ٱللهَ وَٱلْبُرْهَانِ عَلَى ذلِكَ بِٱلْعَمَلِ !‏