It is quite common these days to hear people say that God is doing a new thing, or that our old way of doing things is, in fact, not what God had intended at all. People often scoff at tradition, insisting that their interpretation of Scripture is correct. Some of these people even insist that one doesn't even need Scripture anymore, that it is not necessary to line up our experiences and ideas with Scripture and should we dare to compare what they are doing with the Word and point out where it contradicts the Bible they simply insist that God is doing a new thing and that their revelation is correct.
Discussing these matters can be quite frustrating, I know this from first hand experience. It is easy to point fingers and show (even correctly) where they have strayed. But, and I think this is key, we must be sure that our rebukes are done in a spirit of meekness. Often times it is easy to become prideful, more often than not we probably don't even intend for it to happen. But it does happen. The Bible is clear, as we admonish those around us to turn to the true Gospel, to the true God, we must not allow our pride to become puffed up. Christ was not prideful or arrogant as He brought the truth, rather He coupled truth with grace in His message.
And the Word was made flesh, and dwelt among us, (and we beheld his glory, the glory as of the only begotten of the Father,) full of grace and truth. (John 1:14, emphasis mine)
Likewise we are called to bring the truth, but to bring it in a way that serves. Sometimes people do need a swift kick in the pants, other times a gentler way may be necessary, in all situations we are to serve in a way that glorifies God. Repeatedly we are called to check our own hearts, to be sure we are serving consistently in a humble way, and then if the lost reject what we say it will not be because we put a bad witness out there.
Nevertheless the foundation of God standeth sure, having this seal, The Lord knoweth them that are his. And, Let every one that nameth the name of Christ depart from iniquity. (2 Timothy 2:19, emphasis mine)
And the servant of the Lord must not strive; but be gentle unto all men, apt to teach, patient, In meekness instructing those that oppose themselves; if God peradventure will give them repentance to the acknowledging of the truth; And that they may recover themselves out of the snare of the devil, who are taken captive by him at his will. (2 Timothy 2:24-26, emphasis mine)
In all things showing thyself a pattern of good works: in doctrine showing uncorruptness, gravity, sincerity, Sound speech, that cannot be condemned; that he that is of the contrary part may be ashamed, having no evil thing to say of you.(Titus 2:7-8)
God is not doing a new thing, but continuing an old work unto completion. By His Word we are instructed to rebuke false teaching and exhort our brethren to continue on in the true Gospel of the Lord Jesus Christ, but we must do so in a way that shows God's heart.
But continue thou in the things which thou hast learned and hast been assured of, knowing of whom thou hast learned them; And that from a child thou hast known the holy Scriptures, which are able to make thee wise unto salvation through faith which is in Christ Jesus. (2 Timothy 3:14-15)
Preach the word; be instant in season, out of season; reprove, rebuke, exhort with all longsuffering and doctrine. (2 Timothy 4:2, emphasis mine)
Holding fast the faithful word as he hath been taught, that he may be able by sound doctrine both to exhort and to convince the gainsayers. (Titus 1:9)
After all, He doesn't wish that any should perish, but that all would come to repentance through Christ's saving sacrifice on that cross. Right? So, we must be sure to couple the truth with grace, He will lead and show the best way to approach the sin of false teachings. Lest you think I'm saying be overly soft and ignore the dangers of false teachings, let me remind you Christ Himself cut loose on people, but He did so only when necessary. It's all about grace and truth, people. To ignore one to favor the other is to do the beauty of the Gospel a great injustice.