A:
The Bible never describes Cain as black. However, white supremists have identified the 'mark of Cain' (Genesis 4:15) as referring to him as black. Yet the same white supremists accept the biblical Flood story as literally true, meaning that modern black people would have to be descended from Noah, not from Cain.
Genesis 4.
The bible says that Adam and Eve had other children beside Abel and Cain, so Cain married his sister.
You won't. According to the Bible Cain was the son of Adam and Eve. Genesis 4:1 says,"And Adam knew Eve his wife; and she conceived, and bare Cain, and said, I have gotten a man from the LORD."
Tubal-cain was a metal-worker, as the Bible says: And Zillah, she also bare Tubalcain, an instructer of every artificer in brass and iron: and the sister of Tubalcain was Naamah. (Genesis 4.22)
This expression is NOT in the Bible.
Psalm 23.
The bible clearly says Adam had other sons and daughters.
There is nothing in the Bible that says that
The bible clearly says that beside Abel and Cain, Adam had other sons and daughters.
That is a humorous imaginary quote which doesn't occur in the Bible.
The bible mentions Seth, but not all the others. He either married a sister or a close relative.
In St. Matthew chapter 25, goats symbolize the Damned.