The question might have occurred to you as to why we use leavened bread for the Lord’s Supper, when the bread which Jesus used at the Last Supper to institute this sacrament was unleavened. It’s a good question. Since we want the reason for why worship the way we do to be “because Scripture teaches this” instead of “it’s just what’s always been done” an answer is in order.
The Lord’s Supper corresponds with the OT Passover. However, there are points of continuity & discontinuity; the seed has continuity with the flower and the fruit, while a shrewd observer will notice some discontinuity. A seed isn’t the fruit, after all.
In Scripture, leaven sometimes represents sin (Lk. 12:1, Gal. 5:9, 1 Cor. 5:6-8), but not always. Even at the Passover, the prohibition on yeast didn’t represent sin, but rather it marked the need for readiness to swiftly leave Egypt. Jesus likens leaven to the growth of His Kingdom (Lk. 13:21). Several OT sacrifices, particularly peace offering (Lev. 7:13-14), included loaves of leavened bread. In these ceremonial sacrifices the worshippers partook of this bread as part of the covenant feast with God.
The NT writers, when writing about the bread of the Lord’s Supper, opt for the word artos, the generic word for bread, instead of azumos, the specific word for unleavened bread. Meaning the type of bread was of less importance than the sign behind the bread.
But, we have to make a choice one way or another. So again, why leavened bread?
The choice for using leavened bread comes down to the aforementioned discontinuity between the seed of the Passover and the fruit of the Lord’s Supper. While the Passover was eaten in haste, the Kingdom Christ inaugurated is the Kingdom of the Lord of the Sabbath. He’s our rest. The earth is the Lord’s. Every corner of the globe is our inheritance. As true sons & daughters of true Israel, we’ve entered upon true Sabbath rest. Even while the work remains of compelling all nations to come into Christ’s Kingdom, we’re at leisure to let the dough rise.
So come in faith and welcome to Jesus Christ…