don’t get Christianity as a whole confused with Catholicism. many of those beliefs are not according to the Bible and thus are not true Christian beliefs. those are Catholic beliefs, meaning that they come from the remnants of the Roman empire trying to hold on to power and not from the word of Christ. also, anything from the old testament is no longer the rules. the entire point of the new testament is that humans can’t follow the old rules, so pretty much the only rules now are accept God as your savior and try not to be a dick. as a sidenote, yes I know many people who claim to be Christian fail to not be a dick, they are not true Christians. they simply claim to be to justify some prejudice using misquotes of the Bible and rules that stopped applying long before it was even called the Bible.