The theme of what is good
has pervaded the apostle’s writing since 1 Peter 2:11, when he first spelled out the need for Christians to be careful to do the sort of activities for the community that even the unbelieving public recognized were good.
It is the concept illustrated by Abram when he rescued not just Lot from the five victorious kings but the captives from Sodom and Gomorrah (Genesis 14:16). It is the concept that the Lord instructed Jeremiah to share with the exiles: Seek the welfare of the city where I have sent you into exile
(Jeremiah 29:7). See further on 1 Peter 2:12. Peter mentioned the concept directly also in 1 Peter 2:15, 1 Peter 2:20; 1 Peter 3:2, 1 Peter 3:11 (in his quote from Psalm 34).
13 Now who is there to harm you if you are zealous for what is good?