the Baptists because Southern Baptists believed that the Bible very clearly taught that slavery was okay.  They further believed that ministers were allowed to own slaves.  Is the Southern Baptist church a Christian church? 

There is not as much clarity in the Bible on the homosexuality issue as some would like to think.  It very much depends on what criteria you use for interpretation.  And, even then, you have to be very careful that a consistent application of your method doesn't lead you where you don't want to go.

If homosexuality is an abomination as the OT says, then so also is eating shellfish.

In the NT passage, are we supposed to take Paul's culture into account when interpreting or just go with what it says?  If we just go with what it says, then why don't we go with what it says in other places?

Using the Bible alone fails to resolve this issue.

And, AFAIK, there is no requirement for someone to believe homosexuality is a sin in order to be a Christian.