Sexual immorality is nothing new. As Paul introduced people to Jesus, they were often coming from a background where sexual immorality was encouraged. He is making it clear this was not to be true of those who come to Christ. Apparently, when Timothy brings his report of the church in Thessalonica, he tells Paul they are confused about what happens to people who die before Jesus returns. Paul had taught them about what would happen when Jesus returns, but loved ones had probably died in the meantime, and they wanted to know what would happen with them. Paul assures them they will be resurrected, just as Jesus was.
The culture we live in appears to be moving further from God’s standards, especially in the area of sex. Though we may struggle with adjusting to these changing attitudes, the New Testament was actually written in a similar culture. We are called to live according to God’s standard, regardless of what the culture says, and introduce those in the culture to a God who loves everyone, despite their resistance to God’s desires for them.