“While there are literally more than a thousand parables scattered throughout the encyclopedic-sized rabbinic literature, not one fictitious narrative at all close in form to Jesus’s parables has been discovered in ancient Greco-Roman literature. It appears to have been a uniquely Jewish form of teaching in that day.”
Craig Blomberg, The Historical Reliability of the New Testament (Nashville: B&H Academic, 2016), 170. For illustration of this point, Blomberg points in a footnote to Harvey K. McArthur and Robert M. Johnston, They All Spoke in Parables: Rabbinic Parables from the First Centuries of the Christian Era (Grand Rapids: Zondervan, 1990; repr. Eugene, OR: Wipf & Stock, 2014).
Orchard Keeper 