The Bible cannot prove denominations are right or that the names of such are even found in the Bible. The bible does not prove that a man is justified by faith alone, to the exclusion of the love, mercy, and grace of God, repentance of sins, and obedience to the gospel of Christ. The bible does not prove that a person can be saved out of the church as well as in it. The bible cannot prove the doctrines and commandments of men. In fact, the bible cannot prove false doctrine of any kind. However, here are some things you can prove by the Bible.
1. Baptism is essential to salvation from sin. “He who believes and is baptized will be saved” (Mk. 16:16). “Repent, and let everyone of you be baptized in the name of Jesus Christ for the remission of sins” (Acts 2:38). “And now why are you waiting? Arise and be baptized, and wash away your sins, calling on the name of the Lord” (Acts 22:16). “The like figure whereunto even baptism doth also now save us” (1 Pet. 3:21).
2. We are to sing in worship to God. “Speaking to one another in psalms and hymns and spiritual songs, singing and making melody in your heart to the Lord” (Eph. 5:19). “Let the word of Christ dwell in you richly in all wisdom, teaching and admonishing one another in psalms and hymns and spiritual songs, singing with grace in your hearts to the Lord” (Col. 3:16).
3. A child of God can fall from grace or apostatize, and eventually be lost. “You have become estranged from Christ, you who attempt to be justified by the law, you have fallen from grace” (Gal. 5:4). “Therefore let him who thinks he stands take heed lest he fall” (1 Cor. 10:12). “Brethren, if anyone among you wanders from the truth, and someone turns him back, let him know that he who turns a sinner from the error of his way will save a soul from death and cover a multitude of sins” (Jam. 5:19-20).
4. The church is not to provide social meals as one of its works. “What! Do you not have houses to eat and drink in? Or do you despise the church of God and shame those who have nothing? What shall I say to you? Shall I praise you in this? I do not praise you” (1 Cor. 11:22). “But if anyone is hungry, let him eat at home” (1 Cor. 11:34).
5. In benevolent work, the church is to relieve needy saints. “Now concerning the collection for the saints, as I have given orders to the churches of Galatia, even so do ye” (1 Cor. 16:1). “But now I am going to Jerusalem to minister to the saints. For it pleased those of Macedonia and Achaia to make a certain contribution for the poor among the saints who are in Jerusalem” (Rom. 15:25-26 f; 2 Cor. 8-9).
6. There is only one scriptural exception for a man putting away his wife and marrying another. “And I say to you, whoever divorces his wife, except for sexual immorality, and marries another, commits adultery; and whoever marries her who is divorced commits adultery” (Matt. 19:9). “But I say to you that whoever divorces his wife for any reason except for sexual immorality causes her to commit adultery; and whoever marries a woman who is divorced commits adultery” (Matt. 5:32).
7. When a Christian sins, he must repent and confess his sins in order to be forgiven. “. . . for your heart is not right in the sight of God. Repent therefore of this your wickedness, and pray God if perhaps the thought of your heart may be forgiven you” (Acts 8:21-22). “But if we walk in the light as he is in the light, we have fellowship with one another, and the blood of Jesus Christ his Son cleanses us from all sin. . . . If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness” (1 Jn. 1:7,9).
If these things are proven by the Bible (and I believe they are) then, all teaching and practice contrary to them is wrong! The Bible does say, “Prove all things; hold firm that which is good” (1 Thess. 5:21). The bible can’t prove false teaching, but it definitely proves the gospel and doctrine of Christ. Obey and continue in what you can prove by New Testament scripture.