Colossians 3:16 (KJV)
Let the word of Christ dwell in you richly in all wisdom; teaching and admonishing one another in psalms and hymns and spiritual songs, singing with grace in your hearts to the Lord.
We're meant to do life together.
One way to do it is to worship together in a local body of believers. And we are to do it with grace in our hearts. I just happen to think that means extending grace to one another.
After all, we're family!