The apostle Paul condemned slave-trading as sinful (1st Timothy 1:9-10, "kidnappers" in the NKVV). Slave-trading is a sin that would have gotten a Christian ejected from the local assembly. Christianity's basic principles (e.g. Galatians 3:28) undermine involuntary slavery.
The idea, promoted by liberal religious writers, that the Bible's original documents must have had at least some mistakes in them, if only because all human beings are innately mistake-prone, is foolish.
Moving forward toward what God has for you, or for your group, will introduce you to serious conflicts. Blood will be bled, and tears will be shed. But that's still better than rebelliously marching around in a pointless circle for forty years.
Certain national figures like to criticize certain violent international behaviors by saying those behaviors no longer "fit the 21st century." What a delusion. Human nature hasn't changed a fraction since Adam ate the fruit. And neither has God's moral law.
You can tell that a ministry is not controlled by the Spirit of God if it is constantly talking about the Spirit of God. The Spirit of God was sent from heaven to glorify Jesus Christ.
19th century Baptist preacher Charles Spurgeon once said you don't defend the Bible, just like you don't have to defend a lion -- you just let it out. Okay, I understand his intention to honor the power of God's word. Problem is, the Bible itself tells us to defend it. We're supposed to defend the Gospel, which is inseparable from defending the Scripture from which we learn the Gospel. Peter said to be ready to give an answer for the hope that is in us, and Paul said in II Corinthians to tear down every argument that exalts itself against the truth of God. God has assigned to us the task of defending the Gospel and the Bible from which it springs.
Unless you're willing to say that true Christians never knowingly sin, then you have to answer the title-question "Yes." Every time a Christian knowingly sins, that Christian has broken out from under Christ's yoke. If surrender to Christ's Lordship was an automatic, constant, and unchangeable result of being born-again, then Paul had no good reason to write us Romans 12:1, or Peter to write us 1 Peter 3:15a.
I have just read about 21 former Mars Hill Church pastors calling publicly for Mark Driscoll's removal from his pastorate. Before anyone in the Internet world starts complaining that all this should have been done privately, it appears from what we know that there had been quite a fair bit of discreet work done with brother Mark over several years.
Homosexuality is a symptom of something worse. Read Romans 1:21-27.