Matthew 5 -- Is popularly called the Sermon on the Mount, beatitudes, or the "supreme blessedness"

This chapter contains what is popularly called the Sermon on the Mount.(or the beatitudes, or the "supreme blessedness") The teaching here is a discourse on Torah. That will be evident when we see the source of the Words of Yeshua.
Mat 5:1
And when He saw the multitudes, He went up on the mountain; and after He sat down, His disciples came to Him.
Mat 5:2
And opening His mouth He began to teach them, saying,
Mat 5:3
"Blessed are the poor in spirit, for theirs is the kingdom of heaven.

"Blessed are the poor in spirit, for theirs is the kingdom of heaven." The Kingdom of Heaven is the land of redeemed Israel. Who are the "poor in spirit?" They are ones who are humble. They will inherit the Kingdom of Heaven (Lev. 26:41-42, Deut. 8:2-3, 6-9).
Mat 5:4
"Blessed are those who mourn, for they shall be comforted.

We all mourn when we lose a loved one. But that is not to what this passage is referring. This is referring to mourning for one's disobedience to Elohim Isa 51:11-12, 57:15-18, 61:2-3).