You probably didn't want to know this, but ["cross my heart and hope to die"](https://www.dictionary.com/browse/cross-my-heart-and-hope-to-die) is a phrase used to make a promise, often used by parents and children.
Sometimes it is extended by ["stick a needle in my eye"](https://en.m.wiktionary.org/wiki/cross_my_heart_and_hope_to_die,_stick_a_needle_in_my_eye).
Despite being used by children, it probably doesn't fit the theme of the show, so it was changed to "cross my heart and hope to fly, stick a cupcake in my eye".
>Why the pink one so damn goofy đź’€
She is an eldrich multidimensional god of immense power.
Azatoth dreams the universe, Pinkie dreams Azatoth.
And than calls Luna to give it some dreamwalk spanking.
Pinkie is supposed to be that very fun friend who you swear is too old for her antics but she just loves to make people happy to hide her crippling depression.
Wait till you see Maud, Pinkie’s sister. Total opposite.
Yea
Maud Pie: want to hear a rock poem?
She’s just a silly little creature
Goofy ahh horse
That about sums up Pinkie Pie right I think
It's simply in the devious nature of the Pie family to be so hornswogglingly silly and/or goofy. Truly a complete menace.
You probably didn't want to know this, but ["cross my heart and hope to die"](https://www.dictionary.com/browse/cross-my-heart-and-hope-to-die) is a phrase used to make a promise, often used by parents and children. Sometimes it is extended by ["stick a needle in my eye"](https://en.m.wiktionary.org/wiki/cross_my_heart_and_hope_to_die,_stick_a_needle_in_my_eye). Despite being used by children, it probably doesn't fit the theme of the show, so it was changed to "cross my heart and hope to fly, stick a cupcake in my eye".
Exactly, it’s a cute and whimsical play on what’s a rather macabre expression.
Why does this sound like someone from the hood just now discovered ponies.
>Why the pink one so damn goofy đź’€ She is an eldrich multidimensional god of immense power. Azatoth dreams the universe, Pinkie dreams Azatoth. And than calls Luna to give it some dreamwalk spanking.
It's Pinkie, don't question it. :)
 she’s tooooooo silly
Bro is silly as hell
Wait until you see her in hd version.. smiling..
Pink one is best pony
Cross my heart and hope to fly, stick cupcake in my eye. 
She is the happy, bubbly shadow of Discord. Pink shadow, pink pink shadow.
That line was referenced in Harley Quinn Birds of Prey ^ ^
Goofy ahh pinkie pie makes life worth living
Rule number 1 with dealing with Pinkie Pie: never ever break a Pinkie Promise
goofy ahh mf
What the heck did I just read XD
I say that all of the time, to this day. It’s the best way to promise!
She feels very different after Cupcakes and Smile HD
Cross my heart, hope to fly, stick a cupcake in my eye It’s a parody of our saying: cross my heart, hope to die, stick a needle in my eye
Cross my heart and hope to fly, stick a cupcake in my eye The Pinkie Promise
It's why we love her!
“Pony from Ohio” 💀
Pinkie is supposed to be that very fun friend who you swear is too old for her antics but she just loves to make people happy to hide her crippling depression.