Observations during a Christianity Question and Answer Session

I went yet again, for a question and answer session.

This time around, the topic was focused on pre-destined fates of everyone.
According to people, whether you're saved or not in the end does not depend on what you do.
However, you are accountable for your actions.
The discussion was left hanging in what I would call an utter contradiction with foundations being backed up by pure faith.

The Tower of Babel was destructed because humans were trying to play God.
Humans tried to tell God that they were able to reach God with their efforts.
Punishment attributing to their ignorance was bestowed upon them.

Apparently the Old Testament is similar to most of the other religions out there currently.

It speaks of how to earn God's approval to get onto his good side.

The New Testament is of a new covenant or agreement that humans would not need to please God to earn a place in heaven. If you were destined to be accepted into the heavens, then you will be able to walk freely into the realms of serenity; If not, then so be it, you will have to accept your fate.

Believers are distinguished from non- believers by their practices. 

This is so that people can identify them more easily.
An example from the Old Testament: Do not eat shellfish. Do not eat animals with weird looking hooves.

So much so that the believers would want God to come this instant to salvage the whole world and end their suffering, they are also against God coming too early since there are many non- believers out there living in ignorance. Hence, they preach as much as possible and reach out as frequently as they do to try to make them believe, to give them a chance at God, a chance of being salvaged.

I have my thoughts about the Book of Job. 

Though I might reserve it for another day.

Why do humans need to categorise themselves into groups with distinctive characteristics?

Is it because us humans, like the feeling of superiority and eliteness over others?

Why can't we just pray for every single living being the same way since everyone deserves well, fair and equal treatment? Since we ourselves as humans are flawed with sins and are not capable of giving judgements ( E.g. Job was wronged by his friends who thought that the suffering that he was undergoing meant that he must have sinned terribly)?

Why is it when people pray in communities that they say:

'Please pray for my Nana, who has been hospitalised. Oh, and she's not a believer. ' 

A person's a human, no matter what the person's religion is.

The person feels and goes through exactly the same things other homosapiens do.
Why mention religion in a sincere prayer for a sickly loved one? 

It is wrong to go against the superior being.
It is also wrong to treat someone who has shown you much love in a lesser manner.

Just my half a cent.