"May the grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit be with you all." (2 Corinthians 13:14)
Paul gives final warnings before his third visit. This will be established by two or three witnesses. He warned on his second visit and warns now in his absence: he will not spare those who have sinned if they do not repent. They want proof that Christ speaks through him. Christ is not weak in dealing with them but is powerful among them. He was crucified in weakness, yet he lives by God's power. Likewise Paul is weak in him, but in dealing with them he will live by God's power. Examine yourselves to see whether you are in the faith; test yourselves. Do they not realise that Christ Jesus is in them, unless they are failing the test? He hopes they will discover he has not failed the test, and his prayer is for their improvement. For they cannot do anything against the truth, but only for the truth. He is glad to be weak when they are strong.
The call to self-examination is one of the most important practices Paul commends in all his letters. He called for it before receiving the Eucharist in 1 Corinthians 11. He calls for it here as the fundamental act of a mature Christian life. The Catechism identifies the examination of conscience, the regular practice of reviewing one's life before God, as essential to the preparation for the Sacrament of Confession and to the ongoing conversion of the Christian life (CCC 1454).
The letter closes with a final appeal: aim for restoration, comfort one another, agree with one another, live in peace, and the God of love and peace will be with you. Greet one another with a holy kiss. All the saints send their greetings. And then the benediction that has ended Christian worship and been spoken over every congregation in the Church's history: May the grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit be with you all. Three persons, three gifts: grace from the Son, love from the Father, fellowship from the Spirit. The entire economy of salvation is summarised in this single sentence, and it is spoken not as doctrine but as blessing, a gift given to the community as they go out into the world.
Brothers and sisters, examine yourselves to see whether you are in the faith. Not to torment yourselves, but to know the truth of your spiritual condition and to act on it. The self-examination Paul calls for is not morbid introspection but honest inventory: is Christ in me? Is my life consistent with his presence? Where it is not, bring it to God in confession. Where it is, give thanks. Then go out under the blessing of the Trinitarian benediction that covers you.
May the grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit be with us all. Father, cover us with your love. Lord Jesus, pour out your grace on us. Holy Spirit, draw us into your fellowship with one another and with the Trinity. Through Christ our Lord. Amen.