It is in this reign that we first hear of the secular clergy, that is to say, persons who acted as priests but married and did not live in monasteries. Decrees against them were issued in 1394 and 1412, but they continued to increase. It is not clear whether their origin should be sought in a desire to combine the profits of the priesthood with the comforts of the world or in an attempt to evade restrictions as to the number of monks. In later times this second motive was certainly prevalent, but the celibacy of the clergy is not strictly insisted on by Lamaists and a lax observance of monastic rules[686] was common under the Mongol dynasty. The third Ming Emperor, Ch'êng-tsu[687], was educated by a Buddhist priest of literary tastes named Yao Kuang-Hsiao[688], whom he greatly respected and promoted to high office. Nevertheless he enacted restrictions respecting ordination and on one occasion commanded that 1800 young men who presented themselves to take the vows should be enrolled in the army instead. His prefaces and laudatory verses were collected in a small volume and included in the eleventh collection of the Tripitaka[689], called the Northern collection, because it was printed at Peking. It was published with a preface of his own composition and he wrote another to the work called the Liturgy of Kuan-yin[690], and a third introducing selected memoirs of various remarkable monks[691]. His Empress had a vision in which she imagined a sûtra was revealed to her and published the same with an introduction. He was also conspicuously favourable to the Tibetan clergy. In 1403 he sent his head eunuch to Tibet to invite the presence of Tsoṇ-kha-pa, who refused to come himself but sent a celebrated Lama called Halima[692]. On arriving at the capital Halima was ordered to say masses for the Emperor's relatives. These ceremonies were attended by supernatural manifestations and he received as a recognition of his powers the titles of Prince of the Great Precious Law and Buddha of the Western Paradise[693]. His three principal disciples were styled Kuo Shih, and, agreeably to the precedent established under the Yüan dynasty, were made the chief prelates of the whole Buddhist Church. Since this time the Red or Tibetan Clergy have been recognized as having precedence over the Grey or Chinese. In this reign the Chinese made a remarkable attempt to assert their authority in Ceylon. In 1405 a mission was sent with offerings to the Sacred Tooth and when it was ill received a second mission despatched in 1407 captured the king of Ceylon and carried him off as a prisoner to China. Ceylon paid tribute for fifty years, but it does not appear that these proceedings had much importance for religion[694].