Hebrews 13:1 Let brotherly love continue.
NIV says, “Keep on loving one another as brothers and sisters.” Brotherly love is the translation of one Greek word, Philadelphia, spelled just like the city.  “Brotherly love” is a prevalent and important virtue taught by God throughout the NT.
1 Thessalonians 4:9 Now concerning brotherly love you have no need for anyone to write to you, for you yourselves have been taught by God to love one another.  Believers are linked in the common bond of having been saved by the death of Jesus and indwelt by the Holy Spirit. When believers interact, we are not only physically connecting but also, spiritually connecting.