"המלך"
“The King.”

QUESTION: Why did Rabbi Aaron of Karlin (one of the eminent disciples of the Maggid of Mezritch) faint when he began to recite “Hamelech”?

ANSWER: The Gemara (Gittin 56a) relates that when the Roman armies under General Vespasian besieged Jerusalem, Rabban Yochanan ben Zakkai went out of the city to meet Vespasian to intercede on behalf of the Jews. When he appeared before him he said, “Peace be unto you, O King, peace be unto you, O King.” Vespasian said to Rabban Yochanan, “You are liable to death on two accounts. First, I am not a king, and you are mocking me by calling me ‘King.’ Furthermore, if I am a king, why did you not come until today?”

When Rabbi Aaron of Karlin recited “Hamelech” — “The King” — he reflected upon the statement, “If I am a king, why did you not come until today!” and fell into a deep faint.

(מחזור נוסח אר"י)