Why is love for brethren essential in the Christian life?

Love for one another is a foundational command in the Christian life, as emphasized in John 13:34-35. Jesus commanded His disciples to love one another as He has loved them, highlighting that this love serves as a distinguishing mark of true discipleship. Furthermore, in 1 John 4:12, we see that loving our brethren reflects God's love dwelling in us. Christians are not only connected to Christ but also tied together as a body, and this mutual love strengthens and encourages one another in the faith, fulfilling the law of Christ.