# like yeast

Only a little bit of yeast is needed to make a lot of dough rise.

# three measures of flour

This is a large amount of flour, since each measure was about 13 liters. You may need to use a term that your culture uses to measure flour. Alternate translation: "a large amount of flour"

# until all the flour was leavened

When flour dough is leavened, it expands. Alternate translation: "until the whole lump of dough grew big"