A hilarious phrase that is not supposed to be funny, but actually meant to be a G-rated exclamation of surprise or amazement used by LDSers (aka Mormons).
One Mormon girl to another Mormon girl:
"Oh my heck! You're having another baby! That's 14 now isn't it! Joseph Smith would be proud"
an exclamation that can be used in many circumstances. it is a less profane version of "oh my fuckin god" and more positive. it can be used when something is funny, surprising, or maybe dumb.
Peppa: George, we won the lottery!
George: OH MY HECKIN' GOD
George: oops i've spilt your tea
Peppa: ugh oh my heckin god ur cancelled