UNLEAVENED BREAD
They were flat bread cakes, lacking yeast; They are first mentioned in the three men’s visit to Abraham (Gen. 19:3). In the institution of the Passover and the seven-day feast that followed, the presence of leaven in houses is totally prohibited (Ex. 12:8, 15-21).
They were ordered in all the offerings in which bread entered (Lev. 2:11-12), typifying the absence of all corruption in the sacrifice, a figure of that of Christ, with the exception of the peace offering ordered in Lev. 7:13, of thanksgiving, where the imperfect person of the worshiper is accepted.
Throughout Scripture, leaven symbolizes iniquity; This is why, following the type of the festival of unleavened bread, we are exhorted to celebrate the festival not with leaven of malice and wickedness, but with unleavened bread of sincerity and truth (1 Cor. 5:8).