The accusation is sometimes made that Jesus erred when He said that the mustard seed was the smallest of all seeds. People who make this accusation do so by hauling Jesus’s words out of context and acting like He was dictating a section on seed sizes for a science book – which the accusers then demonstrate to be wrong in the view of science.
When Jesus spoke of the mustard seed, I take it He was speaking of what was commonly considered among His contemporaries as the smallest garden seed (since the parables were of plants and growth) at that time and in that region. To portray that as a false belief that creation technically had no smaller seeds is to do violence to His meaning and context…and to really be quite silly.
When my little league baseball coach told us we could swing a bat no less than 28 inches in length, he was correct in the context of our rules at that time and in that place. To portray it as if he had a false belief that there could not exist any bat of less than 28 inches is to do violence to his meaning and context…and to really be quite silly.
The following blog post by Marvin Cotten* gets at the underlying Greek behind Jesus’ teaching and further helps to put His words back in context: A Grain of Truth – Theologica.
(*Source information: Marvin Cotten writes the blog Asphaleia and co-writes the blog To Be Continued…, also called continuationism.com. Marv is associated with Michael Patton the blog Parchment and Pen; see also Theologica which is the site that has the post referenced above.)
And Yet More:
For the true importance of the seed concept, see Jesus Is the Long-Promised Seed.