Challah for Parashat Bo
Door, Hyssop, Blood.
Every week, Julie Seltzer, artist and Torah scribe, bakes a challah depicting an aspect of the week's Torah portion.
Take a bundle of hyssop, dip it in the blood that's in the basin, and put it on the lintel and the two doorposts.
וּלְקַחְתֶּם אֲגֻדַּת אֵזוֹב, וּטְבַלְתֶּם בַּדָּם אֲשֶׁר-בַּסַּף, וְהִגַּעְתֶּם אֶל-הַמַּשְׁקוֹף וְאֶל-שְׁתֵּי הַמְּזוּזת
The Hebrew slaves were instructed to put blood on their doorposts, so that the Angel of Death would know to skip over their houses when meting out the tenth plague--killing of the first born. The "blood" here is beet juice, and when we blessed the bread, we reenacted this instruction.