Friendship characterizes a Christian life and the communion of saints because it is a result of God’s grace to cause, preserve, and sanctify Christians to love one another. A beautiful picture of faithful friendship in the church is in Paul’s letter to Philemon. Faithful friendship can be seen in Philemon’s love for the church, Paul’s love for Philemon, and Paul’s appeal for Philemon to love Onesimus. In Philemon 4–7, Paul recognizes, in thanksgiving to God, Philemon’s example in his faith in Christ by his love for the saints, which has refreshed the hearts of the church. In these verses, Paul rejoices in Philemon’s friendship with Christ and the church. This thanksgiving should be appreciated within the context of the mention of God’s grace enclosing Paul’s appeal in verses 4 and 25. Grace is the cause, source, and foundation of the friendships in the church. The heart of Paul’s appeal is his identification and explanation that he loves Onesimus because Onesimus is in Christ. Onesimus’ union and communion with Christ are the causes of Paul’s love and friendship with Onesimus. Paul’s love for Onesimus and Paul’s appeal for Philemon to love Onesimus are rooted, grounded, and sourced in God’s grace.
A faithful Christian and a faithful church ought to love one another in friendship because it is a way of grateful obedience to the Great Commandment. In addition to being a godly virtue and a fruit of God’s grace, friendship is a doxological duty for the Christian to gratefully obey. In 1 John 4:7–21, friendship is not an option; rather, it is a result of obeying the Great Commandment, loving God and one another according to God’s law. As Philemon was obligated to love Onesimus because Onesimus belonged to Christ, Christians are obligated to love one another in friendship, because we commonly belong to Christ. We belong to one another with the duty to reciprocate love, share our gifts, and supplement our faith with love in holy friendship within the church. John exhorts in 1 John 4:19–21:
We love because he first loved us. If anyone says, “I love God,” and hates his brother, he is a liar; for he who does not love his brother whom he has seen cannot love God whom he has not seen. And this commandment we have from him: whoever loves God must also love his brother.
Friends, we love one another in friendship by faith according to God’s law for His glory.
If love is greater than faith and hope, friendship is a way of loving rightly. Thus, friendship should be regarded with the highest importance. Godly friendship is a gift of God’s grace for the good of the church. In the Orthodox Presbyterian Church, every member vows, “Do you acknowledge Jesus Christ as your sovereign Lord and do you promise, in reliance on the grace of God, to serve him with all that is in you, to forsake the world, putting to death your old nature and to lead a godly life?” Godly friendship fulfills this vow in doctrine and life. A faithful Christian can promote the peace, purity, and unity of the church by giving the grace received from God to one another in love. Faithful Christians virtuously, graciously, and gratefully obey God’s command to love one another by sharing, communing, and fellowshipping in God’s grace. An essential truth about Christian character is that a Christian is a faithful friend because Christ is a faithful friend. Friendship is important because love is greatest. God is love, and He is glorified by Christians who love wisely, rightly, and well in holy friendship. This love promotes the peace, purity, and unity of the church. As Paul writes in 1 Corinthians 13:13, “So now faith, hope, and love abide, these three; but the greatest of these is love.”