Look at what Paul wrote:
Brothers and sisters, we urge you to warn those who are lazy. Encourage those who are timid. Take tender care of those who are weak. Be patient with everyone. See that no one pays back evil for evil, but always try to do good to each other and to everyone else. Always be joyful. Keep on praying. No matter what happens, always be thankful, for this is God's will for you who belong to Christ Jesus. Do not stifle the Holy Spirit. Do not scoff at prophecies, but test everything that is said. Hold on to what is good.
1 Thessalonians 5: 14-21
If it isn't in the Bible, it isn't true. The Bible is God's handbook for life all that is true. Christ said he was the Truth, the Life, and the Way.
When I hear your claim about "25,000" different Christian sects and then the strange comparison to David Koresh, I really must shake my head. Do you believe that? The Bible says we Christians are of the same body. I know Methodists, Baptists, and Presbyterians who all volunteer at the same drug and alcohol center. They certainly behave as Christ's sheep.
I was raised a Catholic. But, I never knew who Christ was. It was one of those "25,000" sect radical snake handling Protestants that read a Bible to me. Then, I discovered that this Christ is alive.
Tell me, why are you so quick to criticize these faiths that are not under Rome? What have they done that is not Biblical?
Simple. You cannot have 25,000 versions of the Truth or Churches. Jesus the Christ is Truth and founded one Church to promote his scriptural teachings. It was the Catholic Church that gave us the bible where certain writings were included as authentic and others were cast away.
Cardinal Newman was considered a pillar of the Protestants and a scholar and Christian theologian without peer at the time of his conversion to Catholicism. I recommend his book: “The Catholic Church” that irrefutably makes the case you are disputing. Of course we must love our neighbor- Christians and non-Christians alike. Yet continue to pray that they not follow false prophets and doctrines.