Was Goliath was a descendant of 'Orpah.

From a strict biblical and Messianic Jewish perspective using David H. Stern’s Complete Jewish Bible (CJB) translation and style, there is no direct Bible verse that explicitly states Goliath was a descendant of 'Orpah.

However, this widely shared account is heavily anchored in Jewish Oral Tradition (the Talmud and Midrash), which Messianic scholarship frequently engages with to contextualize the Tanakh (Old Testament) and the lineage of Yeshua the Messiah. 

Here is how this understanding breaks down between the written Text (Torah Shebiktav) and the Oral Tradition (Torah Shebe’al Peh).

1. The Written Text (The Scriptural Foundations)

In the Tanakh, the two figures are separated by generations and geographies, but Scripture does provide the structural framework that later Sages connected.

• 'Orpah’s Departure: In the Book of Rut (Ruth), 'Orpah turns back from Naomi and returns to her pagan roots:

  "Again they wept aloud. Then 'Orpah kissed her mother-in-law good-bye. But Rut stuck with her. Naomi said, 'Look, your sister-in-law has gone back to her people and to her god; go back after your sister-in-law.'" (Rut/Ruth 1:14-15, CJB)

• Goliath’s Lineage: In the accounts of David's wars, the giants of Gath are recorded as descending from a figure or people group named Harafah (or Rapha):

  "These four were born to Harafah in Gat, and they fell by the hand of David and by the hand of his servants." (2 Shmu’el/2 Samuel 21:22, CJB; see also 1 Shmu'el 17:4)

2. The Rabbinic & Messianic Connection

Because the Holy Scriptures do not explicitly trace 'Orpah's children into Philistia, the connection comes entirely from the Sages of Israel.

• The Talmudic Equation: In Talmud Sotah 42b, the Sages explicitly declare that Harafah is another name for 'Orpah. The rabbis teach that because 'Orpah shed four tears when parting from Naomi, she was rewarded with four giant sons, one of whom was Goliath. 
• The Early Account: The earliest written mention of this appears in the first-century text Biblical Antiquities (Pseudo-Philo 61:6), which records David taunting Goliath on the battlefield: "Were not the two women from whom you and I were born sisters? And your mother was Orpah and my mother Ruth..." 

3. The Messianic Significance

From a Messianic perspective, this classic midrash is highly instructive. It frames the battle between David and Goliath not merely as a clash of physical warriors, but as a cosmic spiritual choice cascading down through generations. 

Ancestress	The Choice Made	The Messianic Outworking
Rut (Ruth)	Clung to Naomi, crossed into Israel, and embraced the God of Abraham.	Became the great-grandmother of King David, establishing the royal lineage that directly brought forth Yeshua the Messiah.
'Orpah	Kissed Naomi but turned back (oref, meaning the back of the neck) to the gods of Moab.	Her lineage drifted into the ultimate enemies of Israel (the Philistines), culminating in Goliath, who openly defied the armies of the Living God.

Thus, while you cannot point to a specific verse in the CJB to prove the genealogy genealogically, the narrative functions in Messianic thought as a powerful illustration of how a single decision to follow or forsake the God of Israel echoes throughout eternity. 

In Jewish tradition and Rabbinic midrash, Harafah (also spelled Harapha or Raphah) is identified as the same person as Orpah from the Book of Ruth. 

Biblical and Rabbinic Tradition

Identification: Rabbinic literature (such as in the Talmud, Tractate Sotah 42b) connects Orpah—Ruth's Moabite sister-in-law who turned back to her homeland instead of following Naomi—with Harafah (2 Samuel 21:22). 
Mother of Giants: In these legends, Harafah is described as the mother of the giant warriors of Gath, including Goliath.
Etymology: The name Harafah in Hebrew bears a close resemblance to Orpah, forming the basis for the rabbinic link between the two figures.