釋氏要覽 1.401

1.401

四分律云。明相出始得食粥。餘皆非時○婆沙論云。明相有三。初日照剡部樹身。天作黑色。二日照樹葉。天作青色。三日過樹天作白色。三色中取白色為正時。須舒手見掌文分明。始得食粥。

The Sifen lü says: Only when the sign of dawn appears may one eat gruel; all other times are improper times. / The Vibhāṣā-śāstra states: There are three signs of dawn: First, the sun shines on the trunk of the jambu tree, and the sky becomes black. Second, the sun shines on the leaves of the tree, and the sky becomes blue-green. Third, the sun passes above the tree, and the sky becomes white. Among the three colours, the white colour is taken as the proper time. One must extend one's hand and see the lines of the palm clearly; only then may one eat gruel.