“By this everyone will know that you are My disciples, if you love one another.” — John 13:35
In the last study –The Sign of a Disciple – Bearing Fruit – we saw that true discipleship produces visible fruit, which is the evidence of Christ’s life flowing through us. But Jesus taught that all genuine fruit grows from a single root: love. Every act of patience, kindness, service, or forgiveness is ultimately the expression of His love at work within us. With this command to “love one another,” Jesus brings His disciples to the heart of the matter. Love is not just one fruit among many; it is the essence of them all. In this study, we’ll explore how love becomes the defining mark of a disciple and the clearest reflection of God’s Kingdom on earth.
The night before His crucifixion, Jesus gathered His disciples in the upper room for one final meal. After washing their feet, He gave them a new commandment: love one another as He had loved them. The timing of this command was significant. Within hours, Jesus would demonstrate the ultimate expression of love on the cross
He wanted His followers to understand that love was not merely a feeling or principle but the defining mark of discipleship. The world would not recognize His followers by their theology, ceremonies, or words alone, but by their love. This love, that reflected the heart of Christ Himself, is the centrality of His teaching.
In fact, Jesus firmly affirmed that the two most important commands are to love God and to love others as ourselves.
The Example of Christ’s Love
Jesus did not simply tell His disciples to love; He showed them. Earlier that evening, He had knelt down, took a towel, and washed their feet. It was an act reserved for the lowest servant. This was love in action: humble, self-giving, and practical. In a world obsessed with status and power, Jesus inverted the order of greatness. The greatest among them would be the servant of all. His love did not discriminate, nor was it conditional; He even washed Judas’s feet knowing he would betray Him that very night.
This is the love that Jesus calls us to imitate. He says, “As I have loved you, so you must love one another” (John 13:34). His love is the model and the measure. It is patient with weakness, compassionate toward the broken, and willing to bear the cost of others’ good. Such love is not sentimental; it is sacrificial. It means giving when it is inconvenient, forgiving when it is undeserved, and serving when it goes unnoticed.
When believers love this way, the world catches a glimpse of Jesus. For the body of Christ, loving one another is the core of how we are to interact with others. Without love, all our knowledge, gifts, and efforts are nothing. As Paul reminds us in 1 Corinthians 13, love is the greatest of all virtues because it mirrors the very character of God.
Your Love is the Mark of a Disciple
Jesus said that love would be the unmistakable evidence of true discipleship: “By this everyone will know that you are My disciples, if you love one another.” It is not our doctrine, programs, or traditions that most clearly display Christ to the world, but our relationships. The way we treat one another within the body of Christ is the true mark of a Disciple. When love reigns in the church, it becomes a living testimony of the gospel’s power.
This kind of love cannot be faked. It flows from hearts transformed by the Holy Spirit. Romans 5:5 says that “God’s love has been poured out into our hearts through the Holy Spirit.” As we abide in Christ, His love overflows through us to others. The Holy Spirit softens our hearts, heals divisions, and empowers us to love even when human strength runs out.
This love also validates our witness. The early church grew not because of eloquent preaching or an impressive organization, but because the world saw how believers loved one another. Tertullian, an early Christian writer, famously said that unbelievers would look at the church and say, “See how they love one another.” Love is the action that needs no words. It convinces the skeptical and draws the searching toward Jesus.
Unfortunately, in our day and age, many churches seem to be known for their hate, prejudice, or inability to get along with people who might disagree with them in the non-essentials of the faith. This love that marks us as disciples is tested most when these worldly differences arise. While the world is fractured by divisions – political, cultural, nationality, racial, and social status – the church must show a better way. When we love across boundaries, forgive quickly, and serve selflessly, we reveal that Christ is among us. The love of disciples is meant to provide a glimpse of heaven. A community where grace and mercy wins, and unity flows from humility.
The Call to Love in Action
Loving one another is not an abstract idea; it is a daily choice. It means listening more than we speak, seeking understanding before judgment, and putting others’ needs before our own. In 1 John 3:18, we are told, “Let us not love with words or speech but with actions and in truth.” Love moves beyond emotion into an action.
This love finds its expression in countless ways: offering encouragement to the weary, extending forgiveness to the offender, visiting the lonely, feeding the hungry, and praying for those who are hurting. Sometimes love looks like bold truth spoken in gentleness; other times it looks like quiet service behind the scenes. Whatever form it takes, it always points to Christ.
Jesus described this kind of love as new — not because love itself was new, but because He gave it new depth and dimension. His love was radical, boundary-breaking, and redemptive. He loved enemies, touched outcasts, and restored the fallen. When His followers love this way, they continue His mission in the world. Love becomes the bridge by which others encounter the living Christ.
What this Means for Disciples Today
For disciples today, the command to love one another is as urgent as ever. In an age marked by division and self-interest, genuine love is revolutionary. It begins in the church, where we are called to be a family united by grace rather than preference. Every time we choose compassion over criticism, reconciliation over resentment, and generosity over greed, we make the invisible Christ visible.
Loving one another also requires humility. We cannot love from a place of superiority or self-righteousness. True love flows from gratitude, the recognition that we, too, have been loved undeservingly. When we remember how Christ loved us at our worst, it becomes easier to extend that same grace to others.
This love is not confined to those who are easy to love. Jesus told His followers to love even their enemies (Matthew 5:44). For the disciple, love knows no boundaries. It reaches beyond comfort zones, crosses cultural lines, and forgives seventy times seven. Such love may be costly, but it is the truest evidence that we belong to Him.
In the end, love is not simply something we do; it is who we become. As Christ’s love takes root in our hearts, it transforms us into His likeness. The more we love, the more we reflect the One who first loved us. It is the heart of discipleship. It means for us to walk in the way of love, just as Christ loved us and gave Himself up for us.
Love is never content to stay emotional or sentimental; it must take form in action. Jesus showed this the night He washed His disciples’ feet demonstrating that love serves. The measure of our love for God is revealed in how we treat others. In the next study, – A Disciple is a Servant – we’ll see how the heart of a disciple expresses their love through humble service, following the example of the One who came “not to be served, but to serve.”
Questions for Reflection and Discussion
Why do you think Jesus said that love would be the identifying mark of His disciples?
What makes this form of love different from the world’s definition of love?
In what ways did Jesus model love among His disciples, especially in the moments leading up to the cross?
How does His example challenge our ideas of what it means to love others?
Read John 15:12–13.
What does it mean to love one another “as I have loved you”? How does this kind of love go beyond feelings or words?
Why can love among believers be one of the hardest things to live out?
What obstacles, such as pride, unforgiveness, or misunderstanding, often get in the way, and how can we overcome them?
Think about someone in your life or church who is difficult to love.
What would it look like to show Christlike love to that person this week in a tangible way?
Love in the Kingdom of God is active and sacrificial.
What are some practical ways we can demonstrate this kind of love in our homes, workplaces, or communities?
Jesus said that love is what proves our discipleship to the watching world.
How can our unity and compassion as followers of Christ become a testimony that draws others to Him?
My name is Michael Adkins. For several decades I’ve been studying Scripture, developing discipleship resources, and teaching others how to walk more closely with Christ. Currently, I serve as the Discipleship Pathway Leader at Riverside International Church in Cascais, Portugal, where my passion is helping believers grow into mature disciples who live out their faith in everyday life.