Of the very few references compared to other so called sins, they are;
1. Doubted by scholars on the subject to have been translated accurately. Languages change, if such books aren't updated regularly and accurately, they can lose a lot of meaning.
2. Just as anything else in the bible, -written by people-. Read that nice and slow. Humans are subject to error and bias, especially when translating and creating new versions of things over the years.
3. One of many things the bible supposedly condemns that is part of common accepted life. If you ever read it, and I suggest reading many different versions (and translations if you know other languages), studying them, etc, you'll realize quite a few things in there are condemned, things that specifically are even considered normal and ok.
4. Not something that should effect the law. Assuming you don't live in a theocracy where your religion controls the government, of course. Marriage is a secular, legal document in places such as America, England, Australia, pretty much anywhere that isn't a theocracy. This is something you can even verify with your local government yourself. A church may reserve to the right to deny anyone they wish from marrying at that specific church, however a religion does not reserve the right to tell the government who can and cannot marry.
5. Not something your religious figure sounds like he'd condemn, considering it does absolutely nothing to harm anyone or deprive them nor others of their rights nor privacy. After all, he is displayed as this "omni-reasonable" sort of person that wouldn't consider such things any worse than a kid lying that they finished all their broccoli when they really ate all but one, if he had to consider it bad at all.