In his book, Not Even A Hint, Joshua Harris makes some insightful statements about why it is important that we keep ourselves accountable to one another. He says, "The Christian life is something we do together. In Ephesians 4:29, God tells us to build each other up with our words, and later He instructs us to speak to one another with psalms, hymns and spiritual songs (5:19). We need other Christians to speak, sing, and sometimes shout the truths of God’s Word to us. We need others to pray for us when we’re in the midst of temptation. We need friends who will hold on to us when we’re ready to give up. We need friends who will challenge and even rebuke us when we’re indulging in sin" (p.134).
He’s right! All of us need to be accountable. That is the purpose of the "one another’s" in the New Testament. We are to have peace with one another (Mk.9:50), be kindly affectionate to one another (Rom.12:10), give preference to one another (Rom.12:10), be of the same mind toward one another (Rom.12:16), receive one another (Rom.15:7), admonish one another (Rom.15:14; Col.3:16), greet one another (Rom.16:16), have the same care for one another (1 Cor.12:25), serve one another (Gal.5:13), bear with one another (Eph.4:2), be kind to one another (Eph.4:32), forgive one another (Col.3:13), comfort one another (1 Thess.4:18), edify one another (1 Thess.5:11), exhort one another (Heb.3:13), consider one another (Heb.10:24) and love one another. You cannot do any of these "one another's" out without being accountable with one other. I believe that's the Holy Spirit's point with the "one another's. "