1This is the third time I am coming to you. “At the mouth of two or three witnesses shall every word be established.” 2I have warned previously, and I warn again, as when I was present the second time, so now, being absent, I write to those who have sinned before now and to all the rest that if I come again, I will not spare, 3seeing that you seek a proof of Christ who speaks in me who is not weak, but is powerful in you. 4For he was crucified through weakness, yet he lives through the power of God. For we also are weak in him, but we will live with him through the power of God toward you.
5Examine your own selves, whether you are in the faith. Test your own selves. Or don’t you know about your own selves, that Jesus Christ is in you?—unless indeed you are disqualified. 6But I hope that you will know that we aren’t disqualified.
7Now I pray to God that you do no evil; not that we may appear approved, but that you may do that which is honorable, though we may seem to have failed. 8For we can do nothing against the truth, but for the truth. 9For we rejoice when we are weak and you are strong. We also pray for this: your becoming perfect. 10For this cause I write these things while absent, that I may not deal sharply when present, according to the authority which the Lord gave me for building up and not for tearing down.
11Finally, brothers, rejoice! Be perfected. Be comforted. Be of the same mind. Live in peace, and the God of love and peace will be with you. 12Greet one another with a holy kiss.
13All the saints greet you.
14The grace of the Lord Jesus Christ, God’s love, and the fellowship of the Holy Spirit be with you all. Amen.
Faith (Gk. πίστις, pistis). (2:8; Matt 8:10; 9:2, 21:21, Mark 2:5, 11:22, Luke 7:9, 18:42, Acts 11:24, 24:24; Rom 3:22, 25, 12:3; 1Cor 13:2, 2Cor 5:7, 13:5, Gal 1:23, 5:6, Eph 4:13, Phil 3:9, Col 2:5, 1Thess 1:3, 2Thess 3:2, 1 Tim 3:9, 6:12, 2 Tim 2:18, 4:7, Tit 2:2, Phlm 5, Heb 6:1, 11:6; James 2:14, 1Pet 5:9, 2 Pet 1:5, Jn 5:4, Jude 3, Rev 2:19, 14:12) Strong’s 4102
This word, very common in the NT (243 times), can mean, 1) that which evokes faith, “faithful,” 2) “trust, confidence, faith,” 3) “body of faith, teaching.” It is a noun of action—related to the cognate verb πιστεύω (pisteuo) to “believe. It is hard to overstate the importance of this word to Christian theology, since relationship between humans and God is always dependent on faith. This verse uses the word in the second sense of “trust, confidence, faith.” Here, the reference is to saving faith, which amounts to trust in the person of Jesus (God—John 1:12; Eph 1:15) and the message of the Gospel (Jesus’ death and resurrection—1 Cor 15:1-5). Saving faith depends on knowing certain information, but also necessarily goes beyond believing these things to be true, to placing personal confidence and trust in what and who is known. In this verse, grace is the cause of salvation; faith is the means.