One of the points of using parables is to create a memorable visual image related to the truth that the parable is meant to reveal. The other short parable in Sunday's Gospel is the parable of the mustard seed. In the parable, the mustard seed is called the smallest of seeds, and at 1-2 mm across it might just be the smallest. The mustard plant that it grows into is described as a large bush that birds nest in.
So I went to my local farmer's market today and I had this conversation with one of the herb growers:
Me: "How big will your mustard plants get?"
Farmer: "About 3, 3 1/2 feet tall."
Me: "Do birds ever nest in them?"
Farmer (looking at me oddly): "No. Is this that Bible thing?" (apparently I wasn't the first person to ask)
Farmer: "Well, the ones in Israel grow into trees. These are annuals, they don't."
According to my local herb growers, mustard trees are actually a thing. So the visual for the parable is something very big coming from something very small. More on Sunday’s parables tomorrow.