I'm sure the answer would be: "Yeah but they couldn't have foreseen how the modern world works 2000 years ago. We need to adapt to the ti... Hang on did you say we can have slaves again?"

This is the problem. It doesn't matter. For every interpretation one may have, someone else has an interpretation somewhere else in the scriptures that says the exact opposite according to them. The book itself is such a giant catchall for any motive one may have it's almost comical at this point. Virtually anyone can use it as evidence of support for or against just about anything.

And their version of the Second Amendment is four words long.

Matthew 6:5-6 "And when you pray, do not be like the hypocrites, for they love to pray standing in the synagogues and on the street corners to be seen by others. Truly I tell you, they have received their reward in full. But when you pray, go into your room, close the door and pray to your Father, who is unseen. Then your Father, who sees what is done in secret, will reward you."

It's the foundation of his argument that Christians shouldn't impose religion upon others but should lead by example.

In the video, he talks about why he considers the bill antithetical to Christian beliefs and quotes Mathew 6:5 to bring his point home.

Probably Ezekiel 23:20

That just leads to another debate of who wrote the damn thing.

Hint: It wasn't God or Jesus, but it won't stop them from guessing those two first.

But they (the right) usually quote it by removing all context and by only using snippets of the text so there's no interpretation required, in which case it's very easy to retort by using the same tactic or by quoting the whole passage.

Heck, just telling them that "it's written all over the place in the Bible that only God has the ability to judge" takes care of most of their message.