Molière
The Impostures of Scapin (Act 2 Scene 4)
                                                LÉANDRE (alone).

LEA
To betray me after that fashion! A rascal who for so many reasons should be the first to keep secret what I trust him with! To go and tell everything to my father! Ah! I swear by all that is dear to me not to let such villainy go unpunished.