If someone is a non believer, we proclaim the gospel to them and love them. We don't discriminate. If they reject Jesus, though, they will go to hell for their sin. Homosexuality is a sin, but we love them, and proclaim the gospel to them. The verse in Timothy is specifically talking about women having authority over men in a church. Women are more persuasive than men, so if a female church leader falls into a false teaching, she could more easily persuade the men and the whole church into that teaching. It's a safeguard to the true gospel. And as far as slavery in ancient Israel, it was completely different than the American south slavery. There are a myriad of rules as to how slaves can be treated. And Jesus even states that there are things in the mosaic law that weren't God's original intent, but that he allowed because of the hardness of the peoples hearts. He knew trying to outright ban a practice that was deeply imbedded in the culture wouldn't work. It's like telling horny teenagers that they're only option it abstinence. It's definitely the best option for preventing pregnancy and stds, but they aren't going to listen. So, we teach them about birth control and set reasonable boundaries.