1 Peter 3:8-12 (ESV)
Finally, all of you, have unity of mind, sympathy, brotherly love, a tender heart, and a humble mind.  Do not repay evil for evil or reviling for reviling, but on the contrary, bless, for to this you were called, that you may obtain a blessing.  For
"Whoever desires to love life
and see good days,
let him keep his tongue from evil
and his lips from speaking deceit;
 let him turn away from evil and do good;
let him seek peace and pursue it.
 For the eyes of the Lord are on the righteous,
and his ears are open to their prayer.
But the face of the Lord is against those who do evil."
Peter turns his attention from the family, to the congregational family. Just as families so often have trouble among siblings, and between husband and wife. So are congregations often fraught with this. And what starts small can plague a congregation for decades, and not in a good way. Infighting doesn’t help a congregation. It definitely does not help a congregation to reach out to the community about them. Disagreements will arise in a congregation. Sometimes it is even helpful to have some honest discussion concerning disagreements. But the conversation ought to be held in a manner where personal insults are not thrown about. And when someone does throw one at you, keep in mind you don’t have to return it.