Christians do that. Funny thing is, he's suggesting that you have to follow what the bible says in order to be Christian, yet the bible says "Judge not lest ye be judged first" meaning since he judged, disobeying the bible, he is not a Christian. Truthfully not a soul on this planet actually listens or believes in the bible or Jesus and I can prove that shyt easy.
The bible does give recourse for correction, judging though is a no, no. I can correctly and justly tell someone they're wrong without "judging" them, that's to say without spiritually writing them off.
2 Timothy 4:2
Preach the word; be ready in season and out of season; reprove, rebuke, and exhort, with complete patience and teaching.
2 Thessalonians 3:15
Do not regard him as an enemy, but warn him as a brother.
Romans 16:17
I appeal to you, brothers, to watch out for those who cause divisions and create obstacles contrary to the doctrine that you have been taught; avoid them.
Specifically in regards to JW's....
2 John 1:7-10
For many deceivers have gone out into the world, those who do not confess the coming of Jesus Christ in the flesh. Such a one is the deceiver and the antichrist. Watch yourselves, so that you may not lose what we have worked for, but may win a full reward. Everyone who goes on ahead and does not abide in the teaching of Christ, does not have God. Whoever abides in the teaching has both the Father and the Son.
Again, given that the definition of Christianity is the belief in the divinity of JC (at a minimum) Here is really where we should be looking because it applies specifically to Catholicism in regards to their "Christianity" as well as to "which group got it right"
Romans 14:1-23
As for the one who is weak in faith, welcome him, but not to quarrel over opinions. One person believes he may eat anything, while the weak person eats only vegetables. Let not the one who eats despise the one who abstains, and let not the one who abstains pass judgment on the one who eats, for God has welcomed him. Who are you to pass judgment on the servant of another? It is before his own master that he stands or falls. And he will be upheld, for the Lord is able to make him stand. One person esteems one day as better than another, while another esteems all days alike. Each one should be fully convinced in his own mind.
As "brothers" in Christ the "details" or "opinions" on certain things should not hold you up, nor should they cause you "quarrel", the relationship you have with God is your own personal relationship, while you can teach and preach and rebuke and correct, ultimately everyone stands before the master alone and that personal relationship is judged.
For those who are staunch unbelievers and perpetual posters of things like this....
Titus 3 10-11
As for a person who stirs up division, after warning him once and then twice, have nothing more to do with him, knowing that such a person is warped and sinful; he is self-condemned.
Mathew 10: 14-15
If anyone will not welcome you or listen to your words, leave that home or town and shake the dust off your feet. Truly I tell you, it will be more bearable for Sodom and Gomorrah on the day of judgment than for that town.
what really more do we have to speak on?