How we cite our quotes: (Day.Story.Page)
Quote #1
'[...] whoever desires to live a good and honest life is obliged to shun as best he may every possible motive for behaving otherwise. I myself, being one who desires to live a thoroughly honest life, have come all this way in the clothes you see me wearing, ostensibly to seek Your Holiness's blessing for my marriage. But in reality, I have fled, taking with me a considerable part of the treasures belonging to my father, the King of England, for he was planning to marry me to the King of Scotland, who is a very old man whereas I myself am a young girl, as you can see.' (II.3.89, Pampinea's tale of Alessandro and the Abbot)
Holy contradictions, Batman! The English princess (a.k.a. the Abbot) has to be very diplomatic when addressing Pope Boniface, hence her apparently hypocritical explanation of how much she normally hates deception. If you're careful, you can see several levels of subterfuge here: lying to Daddy, gender-swapping, stealing, and employing a cute gentleman with the intent to marry outside her social milieu. She's in deep, so we're fairly impressed that she and Alessandro escape burning at the stake.
Quote #2
The lady's caterwauling brought several people running, and when they saw her and heard what she was shouting about, they were convinced she was telling the truth, more especially because they now assumed that the Count had long been exploiting his charm and elegant ways for no other purpose. (II.8.152, Elissa's story of Walter, Count of Antwerp)
Boccaccio works with an old trick when he writes this scene: it's the story of Joseph and Potiphar's wife (Genesis 39). In the biblical tale, Joseph is sold into slavery and becomes the head of his master's household. But the master's wife really digs him and gets miffed when Joseph repulses his advances. She claims he assaulted her and Joe winds up in jail. This is one deception that Boccaccio clearly doesn't find to be justified, and he has the lady repent on her deathbed, restoring the count's honor.
Quote #3
'Oh husband, I've never had such a fright in all my life. Some young man or other came running into the house, with Messer Lambertuccio in pursuit brandishing a dagger. […] he said: "Madam, for God's sake save me from being killed and expiring in your arms." I stood up, and I was just about to ask him who he was and what it was all about when Messer Lambertuccio came charging up the stairs, shouting, "Blackguard, where are you?"'
'You did the right thing, my dear,' said the husband. 'It would have been a very serious matter for us if anyone had been murdered under our own roof.' (VII.6.517)
The most comical stories about deception need a gullible husband, and there are plenty in The Decameron. In this tale, Madonna Isabella is juggling a husband and two lovers, and when one lover, Lambertuccio, interrupts her in bed with the other, uses her "extraordinary presence of mind" to cook up a story on the spot and fool Lambertuccio and her husband at the same time.