妙法蓮華經玄贊 1.108

1.108

梵云孫達羅難陀，此云艶喜，孫陀羅訛也。艶是妻號，色美端嚴無比名艶，喜是自名。簡前牧牛難陀故言艶喜，艶之喜故。是佛親弟，身長一丈五尺二寸，佛到本城二日度之。大勝生主之所生也。

In Sanskrit it is Sundarananda; here it is translated as 'Beauteous Joy'. 'Suntuoluo' is corrupted. 'Beauteous' is the appellation of his wife; her beauty and dignity were peerless, hence called 'Beauteous'. 'Joy' is his own name. To distinguish him from the previous cowherd Nanda, he is called 'Beauteous Joy'—the Joy of the Beauteous One. He was the Buddha's own younger brother, fifteen feet and two inches tall; on the second day after the Buddha arrived at his home city, the Buddha converted him. He was born of Mahāprajāpatī.