How do we know that gentleness is true fruit of the Spirit?

Gentleness is proven to be true fruit of the Spirit through the observable change in our attitudes and behavior towards others. This transformation occurs as we abide in Christ and the Holy Spirit works within us, enabling us to express kindness and patience, even during trials or when dealing with difficult individuals. In John 21, we see Jesus exhibiting gentleness towards Peter after his denial, which exemplifies how gentleness should govern our interactions. This, along with our ability to forgive, demonstrates the presence of the Holy Spirit's work in our lives.