[Fiji Hill]

For centuries, John was far and away the most popular name in the English-speaking world, if not the whole Christian world. And Mary was the most popular girl’s name. However, those names didn’t make the lists—except for Jack, a nickname for John, Molly, a nickname for Mary, and the variant Maria.

[Olog-hai]

Jack can either be considered a diminutive of John (from Hebrew Yohanan) or Jacob (from Hebrew Ya’akov).

Mary of course (as well as Marie, Maria, Molly et al) is derived from Hebrew Miriam.