What does the Bible say about the necessity of love for Christians?

In Revelation 2:1-7, the letter to the church at Ephesus highlights the importance of love as essential in the life of a Christian. Jesus commends the church for their works and perseverance but rebukes them for having left their first love. This indicates that love is not just an emotion but an active expression of faith in Christ, as well as a vital indicator of spiritual health in the church. The initial fervor of love for Christ and fellow believers must not wane; it should be central to the believer's life and the functioning of the church.