Known both as the Finger of Og and as Herod’s Pillar, the 12.15-meter-long and approximately 1.75-m -wide column is thought to have been quarried in order to decorate the Second Temple as part of King Herod the Great’s 37-20 BCE restoration and renovation works, during which he also enlarged the Temple Mount.That's one possibility, not the only one. But the chances that it is a finger of Og the giant seem remote.
I have mentioned Herod's Pillar/the finger of Og here, but the current article has more information. For much more on the traditions about the biblical giant Og, see there, plus here, and follow the links.
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