1) If God is going to rapture all righteous people to heaven why does the bible say "... For the upright will live in the land..?
Because
that proverb
is about the Mosaic Covenant.
Explained:
The upright Israelites
will live in the Promised Land
and the blameless
will remain in it.
The particular promise of the Mosaic Covenant that is being discussed in that passage can be summed up as follows:
- For as long as the nation of Israel is obedient to God, God will establish them and protect them and in many ways bless them in the Promised Land
- But if the nation of Israel abandons God, God will bring disaster to the Promised Land and to the Isratelites, up to and including the ultimate punishment of dispossessing the Israelites of the Promised Land
2) Why did Jesus say at Matthew 5:5“Happy are the mild-tempered, since they will inherit the earth“
He was speaking to Jewish people
and he was quoting a proverb
that (again) was describing that same promise of the Mosaic Covenant.
The proverb he was quoting is the following:
https://www.biblegateway.com/passage/?search=psa+37%3A11&version=NASB;NRSV
Note: at a time when the Romans were occupying and ruling the Promised Land and subjugating the Israelites. SO: this promise was extraordinarily important to the Jews living in that region at that time. They were living in the time of punishment promised under Mosaic Covenant, the time of being dispossessed, and they were hoping God would return the Promised Land to them very soon.
3) Why does the Bible say this if those that are right with God are going to be rapture to heaven.
Because the two things have no relevance to each other.
The "Rapture" is a relatively recent Christian doctrine
and is not relevant to the Mosaic Covenant, which covenant is between God and the Jewish people.