A Mitzvah In The Mouth
When you come home on Seder night, you are presumably very hungry. You’ve spent the whole day preparing for the Seder and for Pesach. Chametz is forbidden most of the day. Matzah is forbidden all day.
Mitzvah Principles
Intending Not to Fulfill a Mitzvah in the Gemara
Whether deliberately intending not to fulfill a mitzvah blocks it, and why one should not push away a mitzvah that is right in front of him.