Subhuti said to the Buddha, “What should we call this teaching?”
The Buddha replied, “This Sutra shall be known as
‘The Diamond that Cuts through Illusion’.
By this name is should be read and studied. What does this name mean? This Sutra is hard and sharp, like a diamond that will cut away all delusions and bring one to the other shore of Enlightenment.”
“What do you think, Subhuti? Have I taught any definite teaching in this Sutra?”
“No you have not.”
This is the point at which the Buddha describes what this teaching is called. It is called the Diamond Sutra because of it’s power.