However, this religious isolation was to change during the 7th century. At that time, Silla was at war with the kingdoms of Packche and Koguryo and was under constant invasion from Paekche. In 642 AD, it lost 40 castles to Packche attacks, including the great castle of Taeya near the capital of Silla. This atmosphere dramatically influenced the Buddhist faith of all three kingdoms. Religion became more nationalistic, which tended to intensify the ferocity of the conflicts.
To accelerate the development of this type of national spirit in Silla, King Pop-Hung wanted to recognize Buddhism officially in 527 A.D. He tried to establish it as an official state religion in the area around Kyongju. The attempt was met with vehement opposition by members of the court. In 528 AD, these members of the court pressured the King into agreeing to the execution of a 22-year-old monk named Ichadon to convince them that Buddhism was worthwhile religion. Ichadon's death for his belief in Buddhism resulted in stories of his blood at the execution being white as milk. These stories made him a martyr so the King issued a royal mandate that granted freedom of Buddhist belief. Shortly afterward, Buddhism was accepted by the people. In later years, King Hun-Duk named Ichadon as one of the ten sacred monks of Silla. The study of Buddhism during the reign of King Pop-Hung required the ability to read and write Chinese, so serious study was still confined mainly to monks and the aristocratic population.
Unfortunately, not many places were open for a serious Buddhist student to study in Silla. Therefore, in 650 AD, Won-Hyo and the noted monk Ui-Sang, like other monks of the time, set out to study Buddhism in China. The overland journey took them to Liaotung in Koguryo. Mistaken as spies along the way by several Koguryo sentries, they barely escaped captivity and were able to return to Silla. There is no further record of Won-Hyo traveling to China to study, although one more attempt was made shortly after Packche was defeated in 660 AD by Silla and Tang troops from China. However, such study was not necessary because wisdom was Won-Hyo's from birth and he did not need a teacher. Therefore, he became the only monk of his time who did not study in China.