Numerous Buddhist temples were erected at government expense. Monks and nuns became a normal feature of Korean society. Education and the fine arts were inspired by Buddhist teachings. Powerful abbots were advisors to the king as well as being the teachers of conventional morality. It would be impossible to exaggerate the religious, ethical and cultural effect which a millennium of Buddhist life and thought had on the Korean mind and heart.
What were some of Mahayana Buddhism's lasting contributions to Korean religion? Let me mention five. First, Buddhism is a religion which stresses the need for salvation. According to Gautama's four-fold truth, every man suffers because of his insatiable desires. Men find themselves caught in a ceaseless craving for pleasure which inevitably results in disappointment, pain, frustration and emptiness. What Buddhism offers is a way to escape this meaningless merry-go-round.
Secondly, according to Buddha, liberation or enlightenment can only be achieved as a result of self-discipline and self-denial. There is no easy way out of the human predicament. An individual must curb his sensuous desires and master his body. Gradually but vigorously he must extinguish the craving for physical pleasures. To accomplish this, Buddhists have to practice strenuous moral and intellectual disciplines.
Thirdly, Mahayana Buddhism reinforces the stem ethic of Gautama's teachings with a vivid eschatology. Those who live morally here on earth will be rewarded by the bliss of the Pure Land Paradise. But those who violate the moral commandments will be punished in hell until they have paid for their folly. At least in popular Buddhism (that taught to the laity), the promise of heavenly reward and the threat of hell's torments have been an important stimulus to ethical behavior.
Fourthly, Mahayana Buddhism emphasizes the supreme value of self-sacrifice. The highest ideal is to be a Bodhisattva.