It is important that we understand how important love is given that John stresses it. In a sense, love is what it’s all about. Without it there is no point in believing in the gospel. There is nothing more useless than a church that does not have love. Love is the ultimate ethic and its presence among the brethren is central to the practical vision for the church on Earth.
In 1 John 3 we read that love is the litmus test for a genuine faith in Christ. John tells us that he who has no love in him abideth in death. Also, anyone who hates his brother has no life abiding in him. James writes also that without this love our faith is dead. Our love for the brethren is the indication that we have passed from death unto life. We should look for that in the life of anyone who professes to believe in Jesus.
Love is practical and it’s about what we do for each other. It is not simply nice words and kind feelings. We love each other by meeting needs. A cursory online search I did showed that between 10% and 25% of Christians tithe regularly, depending on denomination and other classifications. While I do not believe that Christians are required to tithe as Jews were that is because we are expected to give 100%, not only of our income but our time, possessions, ability, and effort. Whether someone needs a ride or a home to live in we should be ready and willing to provide. We all have something to offer so we need to be willing to give when the occasion calls for it.
God’s vision for the church is a community of believers who love each other. Without love we are simply autonomous consumers of spiritual entertainment or therapy. The church service becomes a transaction, a show with an admission. Membership has no privileges and I think this necessarily means that discipline becomes impossible because there are no consequences to leaving a church. Without love the church falls apart and becomes ineffective, powerless because the Holy Spirit is not at work. Ultimately this means that the gospel is not being preached and people are not being saved.