P's Rules for Mazzoth. Immediately following the one feast of the Passover came the seven-day pilgrimage feast (cf. Exodus 5:1) of Unleavened Cakes, probably originally an agricultural festival to mark the beginning of barley harvest (pp. 102f.) Falling at the time of year when the Exodus took place, it received a commemorative interpretation, which the plain and quickly prepared mazzoth fitted. The ritual prejudice against leaven (Exodus 12:15) extended to all altar-gifts (Exodus 23:18), and may be due to the persistence in religious ceremonial of primitive usage before leaven was known (Exodus 4:25 *), though the thought that fermentation involved corruption may also have had effect. Later Jews became most scrupulous in searching for the forbidden leaven, and, since unleavened cakes were eaten at the Passover, expelled all leaven before that feast. Paul (1 Corinthians 5:6-8; Galatians 5:9), as well as our Lord (Mark 8:15, but contrast the Parable of the Leaven), makes leaven symbolic of evil. The penalty for disobedience was (Exodus 12:15) excommunication: that soul shall be cut off from Israel (cf. Genesis 17:14; Ezra 10:8). The first and seventh days (Exodus 12:16) were to be an holy convocation (Leviticus 23:2 ff.*), kept with almost the rigour of the Sabbath. The reference to the Exodus as past (Exodus 12:17) shows that Exodus 12:14-17 did not originally follow Exodus 12:1-13, but rather Exodus 12:41, and probably came from another hand. And Exodus 12:18-20 may also be an independent piece, inserted here by R. The reference to the sojourner (Exodus 12:48 *) is the only new feature: he might eat the mazzoth, for that was an act of temperance, not a partaking of holy food. The phraseology in Exodus 12:1-20 is uniformly of the P school.
Exodus 12:14. this day: is not the 14th (Passover) but the 15th (1st of Mazzoth).