Secondly, this request to love one another has an amazing standard. Mutual Christian love is an imitation of Christ. It is possible to read this verse through a theological pair of glasses and respond, ‘It is impossible for me to imitate Christ’s love because his love was perfect and I am sinful.’ Then one can proceed and ignore this command. It is admitted that no Christian can love his fellow disciples to the degree that Christ loved them. But that does not mean that we should not love them as best as we can. In any case, believers have the indwelling Holy Spirit to enable them to love one another in a godly manner, and to grow experiencing that love inwardly and expressing it outwardly.
Thirdly, this request of Jesus contained the promise of an assured success. If they love one another, everyone will know that they are Christ’s disciples. There are several types of evangelism advocated today: personal evangelism, friendship evangelism, tract evangelism, drama etc. It is possible to engage in them without love. But Jesus here promises evangelical success to believers when they love one another. This is the way to convince non-Christians that we are genuine.
It is worth noting that Jesus did not say that making a stand for truth would bring this about. Taking such stands is important, but may not result in a good effect on others; in any case, the world does not understand our beliefs. Nor did he say that engaging in an act of personal sacrifice would necessarily make an impression on society; they cannot read our minds as to why we do particular activities. But he did say that constant, communal, Christlike love would. This is a challenge to our priorities.