Why Did the Non-Buddhists Attain the Fruits, Even the Fourth Fruit, upon Hearing the Buddha's Dharma for the First Time?

The non-Buddhist practitioners had all cultivated the four dhyānas and eight samādhis, subduing and eliminating thought-delusions and afflictions to varying degrees. All that was lacking was the contemplative practice (vipaśyanā-caryā) wisdom regarding the truths of the Four Noble Truths; once that was present, the conditions for seeing the Path would be fulfilled. As the saying goes, everything was ready except the east wind. This east wind refers to the causes and conditions for seeing the Path—once those causes and conditions appeared, one could immediately see the Path. And the cause and condition for their seeing the Path was the Buddha coming to proclaim the truths of the Four Noble Truths. When the conditions for the first fruit were complete, one attained the first fruit; when the conditions for the second fruit were complete, one attained the second fruit; when the conditions for the third fruit were complete, one attained the third fruit; when the conditions for the fourth fruit were complete, one attained the fourth fruit. Therefore, when each person listened to the Buddha's teaching, the fruit they realized differed—the difference lay in the differing conditions for seeing the Path. 

Seeing the Path is like eating the seventh pancake. The non-Buddhist practitioners had already eaten six pancakes and were only seventy to eighty percent full, not yet completely satiated. When they saw the Buddha expound the truths of the Four Noble Truths, they ate the seventh pancake and were instantly full. The first six pancakes were the foundation, lining the stomach; adding one more pancake filled the stomach completely.

Do not merely look at someone's final result; look at the arduous process of their cultivation and how much sweat they shed through diligent effort. If they had not paid an enormous price, had not diligently cultivated the four dhyānas and eight samādhis, they would have no foundation of six pancakes—and even if given six more pancakes, they probably still could not eat their fill and see the Path. Some say that in the question-and-answer exchanges between the Buddha and his disciples, the disciples saw the Path in an instant—just a matter of a few minutes, very easy, not so laborious and troublesome. But do you know that the merit of seeing the Path within those few minutes was accumulated from the countless wholesome roots and merit of the Buddha's disciples? How long did each of them spend eating those six pancakes, and how arduous was it? How great a price did they pay in past lives and this life?

Many people envy athletes who win a gold medal in a single competition—international gold medals, national gold medals—and think how lucky they are, completely failing to see their years of accumulated struggle: how much sweat and tears they shed, how much rest they gave up, how much physical cost they paid, even the cost to life and health, how much grievance they endured, before seizing the gold medal in one stroke on the field of competition. What endeavor in the world or beyond the world is ever so easy—that realizing the fruits would be like eating cabbage? After boundless kalpas of birth-and-death transmigration, with evil karma piled up like mountains and entangling them, how could several minutes or several hours break through the karmic obstructions of birth and death accumulated over countless kalpas, extinguishing the karma of the three evil paths? How could that be possible? Even in dreams one would never dream of such a good thing. Otherwise, why would there be boundless sentient beings in birth and death, rather than boundless Buddhas?