In Genesis 9, Noah said,

“And he said:
‘Blessed be the LORD,
The God of Shem,
And may Canaan be his servant.
May God enlarge Japheth,
And may he dwell in the tents of Shem;
And may Canaan be his servant.'”
(Genesis 9.26, 27).

Here Noah specifies through whom the Messiah shall descend.

The question is to whom does “he” refer in the line: “And may he dwell in the tents of Shem”? Grammatically it can be either God or Japheth.

What would it mean that Japheth would dwell in Shem’s tents? The biblical context points to the interpretation of God.
The NIV made an unfortunate inclusion here, adding “Japheth.”

In Luke 3, the Bible provides the connection between Shem and Jesus the Messiah,

“Now Jesus Himself began His ministry at about thirty years of age, being (as was supposed) the son of Joseph, the son of Heli…” (Luke 3.23).

Then Luke provides names for the genealogy down to verse 36, where we read this,

“…the son of Cainan, the son of Arphaxad, the son of Shem, the son of Noah, the son of Lamech…” (Luke 3.36).

Why was this genealogy important? It became an identifier. The point of all these prophecies, types, and shadows,
provided ways of distinguishing the Messiah, or identifying the Anointed One when He arrived in the world.