That one is pretty easy. The mustard seed was the smallest seed his audience knew about. Jesus repeatedly uses allegories to make larger incredibly profound spiritual points. By using universal real-life experiences to make larger points I believe he knew that it would be easier to by understood centuries and cultures down the road by even the least educated audience. I think it's pretty obvious Jesus' point was that from something incredibly small can come something great and beautiful. The seed analogy, in a largely agrarian world, is an excellent universal analogy (I consider the mustard seed discourse to be an analogy rather than a parable) to make this point. The seed analogy is used in other context throughout the Gospels. Since the mustard was the smallest seed they knew of that's the one Jesus used for his illustration. It would have defeated the purpose to cite the actual, obscure seed that's actually smallest if no one has ever heard of it.
This is exactly what happens when verses are dissected out of context. The point being made at the time wasn't "what's the smallest seed in the world" it was "Just as something tiny as a mustard seed can grow into a large beautiful thing, even so Heaven (or faith) is something which starts out small and grows into something as glorious as the Kingdom of God." The immediately following analogy of the leaven makes the same point using a different analogy.
The thing that irks me is that the question, "Do you believe the Bible should be taken literally?" is an invalid question akin to "When did you stop beating your wife?" Jesus said "I am the vine," yet obviously he did not believe that he was really a plant. Jewish civil law required stoning adulterers. But Christians do not routinely stone people.
The real question that should be asked is, "Do you believe the Bible is the inspired Word of God?" Asking if one takes the Bible literally either shows incredible spiritual, historical and literary ignorance, or a desire to skirt the real issue and entrap the person. I wish there were a candidate smart enough to see through this ruse.
Extremely spot on explanation. You should teach the scriptures, if you don’t already.
That’s what I suspected, but I don’t suppose it’s an adequate enough answer for the Pharisees amoung us.
Great explanation, now, back at the questioner -
what is behind your motivation and obsession with trying to “prove” the Bible to be irrelevant and false?