Luke 11:9-12

See this explained in the notes at Matthew 7:7.

Luke 11:12

“A scorpion” See the notes at Luke 10:19. Dr. Thomson (The Land and the Book, vol. i. p. 379) says: “There is no imaginable likeness between an egg and the ordinary black scorpion of this country, neither in color nor size, nor, when the tail is extended, in shape; but old writers speak of a “white” scorpion, and such a one, with the tail folded up, as in specimens of fossil trilobites, would not look unlike a small egg. Perhaps the contrast, however, refers only to the different properties of the egg and the scorpion, which is sufficiently emphatic.”

Pliny (“N. H.,” xi. 25) says that in Judea the scorpions are about the size of an egg, and not unlike one in shape.