The apostle John reveals that God is the ultimate source of all genuine love. Through Jesus Christ, God demonstrated his perfect love by taking on flesh, living among us, and dying for our sins—loving us first before we ever loved him. This divine love should naturally flow through believers to others, creating assurance in our relationship with Christ. John challenges us with an uncomfortable truth: if we claim to love God but hate others, we are liars, because our love for God must manifest in how we treat people around us.