How do we know that true Christians love one another?

The love Christians have for one another is a clear sign of their new birth and sonship. In 1 John 3:10, John states, 'In this the children of God are manifest, and the children of the devil: whosoever doeth not righteousness is not of God, neither he that loveth not his brother.' This teaching reinforces that love is an essential characteristic of those who belong to God. The love for fellow believers is part of the divine nature bestowed upon them at rebirth. When believers experience God's love, they cannot help but extend that love toward others, reflecting God's own character. Jesus further emphasized this in John 13:35, where He said, 'By this all men will know that you are My disciples, if you have love for one another.'