"Honest to God and hope to die"

[sagehen]

  "honest to God and hope to die."
  "cross my heart and hope to die"

While "cross my heart and hope to die" was certainly in current usage among
the kids I grew up with in Lincoln NE in the 30s,  my impression is that
"honest to God" was more likely to have been heard from adults.  I can't
remember ever hearing "honest to God"  & "and hope to die" together.
A. Murie