Spike, Pinkie and others in “Unfinished Business”

Spike

I'm gonna tell you two a secret. But you have to promise not to tell anyone.

Cross my heart and hope to fly, stick a cupcake in my eye.

Spike

Closer... closer...

Spike

[Confessing tone] I have a crush on Rarity!

[gasps] We won't say a word!

Twilight

Gimme a break, everypony already knows how you-

Twilight! You promised Spike you wouldn't say anything. He trusts you; and losing a friend's trust is the fastest way to lose a friend forever!

Twilight

But..

Forever!