Rabbi Aryeh Lebowitz

The exact nature of the Shemira though is a Machlokas Aposkin.

The Rambam writes on the simplest level that we have to watch the matzo from an early stage and make sure it doesn't become Hametz.

And that's Shemira.

Shemira is just Shemira that it doesn't become Hametz.

Rashi, however, Rashi says no.

It's much more than that.

That it's not sufficient just to watch the matzah and make sure it doesn't become chameis.

You have to make sure, you have to watch the matzah having in mind l'shem matzah.

That you're watching this l'shem mitzvah matzah.

You ever been to a matzah bakery?

What do they do at every step?

They're saying l'shem mitzvah matzah, right?

They're doing everything l'shemah.

And that's shmira.

Shmira means not just I'm protecting it.

I'm just watching, making sure it doesn't become chameitz.

I'm imbuing it with a l'shma.

And Rashi's approach seems supported by the Gemara of Pesach from the Amalchess.

The Gemara says that a person can't be Mekai in his mitzvah of Matzah with the chalos of a carbon toad or the rikikei nazir, because they weren't made l'shma.

What does it mean they weren't made l'shma?