[CubicleGuy]

What would move ancient religious Jews (who cared about the Ten Commandments) to hop in a boat and sail for months over uncharted oceans to parts unknown where they would have no reason to expect ever to see their sacred ancestral land -- let alone any land -- again?

Revelation?

[blam]

"to hop in a boat and sail for months over uncharted oceans to parts unknown

I expect they knew where they were going and how to get there before they left land. (...and how to get back.)