A little yeast makes the whole batch of dough rise! ¹ 

Your boasting is not good. Don’t you know that a little yeast ¹  affects ²  the whole batch of dough?

If the first portion ¹  of the dough offered is holy, then the whole batch is holy, and if the root is holy, so too are the branches. ² 

Clean out the old yeast so that you may be a new batch of dough – you are, in fact, without yeast. For Christ, our Passover lamb, has been sacrificed.