Yeah, according to the bible homosexuality is a sin on part with anything remotely sexual during a menstrual period, eating shellfish or pork or rabbit, mixing fabrics, etc and so on - modern christianity has generally agreed most of the bits in that section no longer apply, but they make an exception for the homosexuality one. It also requires new mothers to avoid church for a month or two, and then make animal sacrifices 0_0
Our "inconsistency" was long in the making. Jesus started it by
declaring all food clean to eat. He also said his role at the time was to
fulfill the law. What that exactly means is heavily debated, since laws can really only be followed, broken, or abolished. My take (most Christians I know believe this too) is the laws were right and good until Jesus's sacrifice, at which point the laws were "fulfilled," and now longer necessary. Much, much later in the book of Acts, the next book after the four gospels of Jesus in the New Testament, and after the Holy Spirit is given freely to the first Jewish Christians, the disciple Peter gets a
vision and is prompted by the Holy Spirit to visit a Roman centurion who converted to Judaism previously.
After that, Peter was questioned by the Jewish Christians about why he defiled himself by eating with Gentiles.
He explains how the Holy Spirit was given to them freely, like it was on the new Jewish Christians early on in Acts. Essentially, God was actively saving and converting people in general, with no distinction between Jews (who followed all the old Testament laws) and Gentiles (who never followed those laws). Everything came together
here. Sorry about the long read, but it's important.