The theological answer, as I learned it, is most clearly spelled out in James 2:14-26, often referenced through the phrase “faith without works is dead”. The short version is: faith in Jesus will save you, not good deeds. However, if you have faith in Jesus, then that faith will manifest itself through good deeds. If someone proclaims their faith but doesn’t act lovingly, then they don’t actually have faith and won’t be saved. So a Christian should be a good person not because being good will save them, but because being good is a result of genuine faith.

In Jesus’s time, there were three different sects of Judaism.

One of them, the Sadducees, allegedly believed there was no life after death and that God didn’t care at all about what people did or didn’t do.

Their answer to your question of following the law is perhaps the most interesting.

They believed that what was put forth as laws were a gift to humanity and that following them inherently led to a better life in the here and now.

While I don’t personally see all of the laws put forward as beneficial, there are certainly instances where that makes a lot of sense.

For example, look at the full version of one of the commandments:

Honor your father and your mother, so that your days may be long in the land that the LORD your God is giving you.

• Exodus 20:12

Would following a commandment to take care of your parents in their old age (‘honor’ here comes from the word for burden) benefit you by setting an example such that when you are old that you too would be taken care of?

This was almost like social security in antiquity, much like the Sabbath was one of the first labor laws preventing working anyone more than 6 days in a row.

There’s something called the overjustification effect, where when you introduce external reward systems for something intrinsically rewarding people over focus on the external and forget the internal benefits. I think a number of religions have serious issues with that.

There’s even a certain irony in Job, named ‘persecuted’ in Hebrew because even though he lived a good life he experienced suffering which it explains by the intervention of Satan, today in the most common language among believers being the exact same word as “to do a task with the expectation of a reward.”

Maybe we’re too focused on the rewards.

TLDR: He doesn’t forgive anyone who sins, he forgives those who repent. Repent not meaning “feeling sorry” as many seem to explain, but actually meaning “to turn away” which means changing fundamentally as a human being. From a bad person to a good person.

Someone who doesn’t change and act good most of the time isn’t repentant, so isn’t forgiven. So basically, you prove it with your actions and how you live your life, not with just words only. By this measurement, Republican “Christians” aren’t repentant and so aren’t forgiven.

Not a Christian anymore, but I used to be for a very long time. Sidebar: “You will know a tree by it’s fruit” AKA you’ll know what kind of person someone is by what they do. Anyone who’s even skimmed the bible (especially the new testament) would easily understand that most conservative “christians” aren’t Christian at all, but rather like the Pharisees (phony religious types) that Jesus constantly argued with and condemned.

Other note: Sikhs actually live the way Christian claim to. I could easily make a “hard to swallow pill” meme which said: “Sikhs are better Christians than actual Christians are.”

I’m catholic, and to me it’s because behaving in a good way will simply make you live better;
the idea is that sin is something that turns you away from God, but being close to God is what makes you truly happy

So even in this life, behaving in a good way would make you live better and happier

IIRC the trick is to get your forgiveness after the last dick move, but before you die. If you mess up the timing, eternal damnation so it’s safer to be good.