I wanted to weigh in on why the Latin Rite Church uses Unleavened Bread, versus the Leavened Bread (as it looks, but is not necessarily the case, in the photo the Rich posts). For my source material, I’ve been listening to Dr. Brant Pitre’s discussion of The Bible and the Mass, 22 CD’s at 80 minutes each, and well worth it, too!
First thing to mention, is that Jesus (as we just heard in last Sunday’s Gospel), conducts the New Passover during the Old Passover, specifically on the Feast of Unleavened Bread. This is the first of the Spring Feasts in Ancient Judaism, and connected with this feast is the Feast of First Fruits, when the first offerings of the field would be offered to God. This was the offering of the purest gifts to God, as Abel sacrificed and offered to God way back in the Old Testament. Happening from 15-22 on the month of Nisan, it was always connected with Passover.
But why unleavened bread? In the ancient Jewish sources, leaven was unclean, less than the pure bread which was unleavened. Leaven is yeast, which consumes the sugars of the bread and produces gas as a waste product. Unleavened bread is pure in that it is only bread and water that has been baked. Hence, this was a sacrifice that was pure, connected with the spotless lamb that was sacrificed for Passover. As the first offerings that man was to give back to God were the best of his offerings, not the leftovers.
Interestingly, the bread sacrifice that was made on the feast of Pentecost or Weeks (7 weeks later) was of leavened bread. Here, God accepts a sacrifice that is less than pure, he accepts that which we offer, even our own sinful selves.
I admit, I had never thought of it in this way, but it draws a great parallel: Jesus is the Firstfruits of the Resurrection, and since he is the new Spotless Lamb, he uses unleavened bread for his Sacrifice. At Pentecost, the birthday of the Church, leavened bread is used for the new growth in the Church which contains sinful members, but since they offer themselves to God now, He will accept. Look for the nuance, even though I may not be stating it clearly enough.
For more, I guess you’ll have to get Dr. Pitre’s CD set, which is available at The Catholic Shop in Madeira…. (shameless plug over). (well, maybe not: he'll be at the Deep in History Conference this year on Pillar and Bulwark)