King Arthur was pensive. Sitting on his throne, with his hand to his chin, the great king looked sad and lost. All was silent in the court. A patina of gloom seemed to have descended on Camelot.
Knights in shining armour looked at knights in matte finish material. Varlets looked at knaves. Maids looked at pages. (Most of whom were pages in charge of clearing out the cobwebs in the palace, otherwise known as web pages).
Only Queen Guinivere looked on proudly. From time to time King Arthur would look at her sadly and shift his gaze back to the floor.
Suddenly there was a puff of light and Merlin the Wizard appeared. The assemblage promptly bowed to the King's revered wizard and advisor.
A quick glance around the room told Merlin that all was not well. With a wave of his hand, he bid them to be gone.
"We wish to have a word with the King in private", he roared and the company dispersed hastily.
"What be it, Arthur? From whence hast this gloom descended, like the fog descendeth on the lake? Excuseth thou the Purple Prose, but we are wearing our Purple gown today" said the Wizard.
"She slept with Gawain last night", said Arthur, gesturing with a thumb towards Guinivere, who continued to stare defiantly.
"I have but purity in my heart, O reverent wizard Merlin" said the Queen.
Merlin gazed at her with his magical vision and turned to Arthur
"'Tis true, Arthur. She speaketh not a lie. Art thou sure thou hast seen what thou thinks though hast seen? That it is not a despicable illusion by Sir Mordred?"
"Ask thou that thyself", snapped King Arthur
"Hast thou, Queen Guinivere, done what Arthur sayeth?"
"I do not deny the event, O Wise Wizard, merely its impropriety"
It took the Wizard a few moments to work this out. Turning to Arthur, Merlin asked
"Hast thou sanctioned this, King Arthur? Art thou NUTS!"
"I swear I have not. She has been sleeping with them all. Last night it was Gawain. The night before it was Galahad. And the other morning I spied Lancelot tippy-toeing out with a smirk on his face. Yet she denies all wrongdoing, and continues unrepentant. We are at a loss"
Merlin smiled sadly. "Arthur, Arthur, thou art a dolt"
"Me? What did I do?"
"Think back, Arthur. Did thou not covenant Guinivere to unhesitatingly and guiltlessly obey thy commands?"
"Yes, but that was to help her overcome her reservations about killing, should any evil being attack her when I am away"
"And rightly so. But is it not beholden upon thee, then, to weigh thy words carefully and evaluate all their implications?"
"I suppose so, but what did I say?" Arthur cried in puzzlement.
"It is always the simplest explanation, mon ami" said Merlin. "What is the last thing thou tellest her before retiring?"
"Has thou kept the milk bottles outside the castle?"
"No, after that"
"Oh!" Said Arthur, for realization had dawned upon him. The wise Merlin had solved it, as usual.
"I tell her to have a good night" he said.
"Exactly", smiled Merlin
Update: I have received an interesting mail from one Prof. Hogsbottom, expert in Arthurian History. He says "Back then, pages in charge of cleaning cobwebs would have a free run of the premises and thus be privy to all kinds of secrets. As a precaution, therefore the pages in charge of the royal chambers would be locked up in special cellars (or crypts) so that they could not relay information accidentally overheard. They were called encrypted pages"