"Jumping Jehosophat" and "Yumpin' Yiminy"--Why the jumping?

[Cohen, Gerald Leonard]

This is a follow-up to the brief "jiminy crickets" discussion. Why do (some) Scandinavian Americans say "Yumpin' yiminy?" Or is this just from the past? Specifically, why the "Yumpin'" (jumping)?

    Similarly, there's "Jumping Jehosophat!" Is there any reason why he's referred to as "jumping"? Am I missing something obvious?

Gerald Cohen