The Misha on page 10B talks of cryptic statment which will prohibit something even if not specifically stated or obligate somone, even if not specifically stated. One of the terms is, f somone says Jerusalem. The unknown author of the mishna (presumably rebbi Meir) says if someone says “jerusalem” they are obligated in an offering. However Rabbi Yehuda says they said nothing.
The Talmud goes into a whole discussion of who is the Mishna and what is the mishna saying about this statment. Frankly the Shikkerdovid was not smart enough to follow the convoluted analysis who is the Mishna following, who is the author and what is the Mishna really saying.
The Shikkerdovid would like to commment however, on the simple idea, that the word or thought or idea of Jerusalem is enought to stimulate the notion of holiness. Simply put, Jerusalem is synonomous with holiness.
The deeper idea is that Jerusalem is not just synomous with holiness, but holiness is synonomous with obligation of an offering. In modern terms, holiness (Jerusalem) is synomous with giving and sharing.