佛祖統紀 2.39

2.39

四十一年（己巳）太子啟王出遊。前至王田。息閻浮樹下。見諸耕人。時淨居天作壤蟲。烏隨啄之。見已悲愍。即便思惟。得四禪地（因果經）王尋太子。見在樹下。一切樹影悉移。唯此樹陰覆太子身。如重雲間忽見明月（菩薩本行經）。

Forty-first year (jisi): The Prince requested the King's permission to go on an excursion. Proceeding forward to the royal fields, he rested under a jambu tree and watched the plowmen. At that time, a Śuddhāvāsa deity transformed into an earthworm, and crows pecked at it. Seeing this, he was moved to pity, and contemplating immediately, attained the stage of the four dhyānas (Sūtra on Cause and Effect). The King searched for the Prince and found him under the tree; all the tree shadows had shifted, but this tree's shade alone remained covering the Prince's body, like suddenly seeing the bright moon amidst dense clouds (Bodhisattva's Former Deeds Sūtra).