四分律行事鈔資持記 3.911

3.911

In the ninth [section]: First, it prohibits practicing occult arts. Regarding the arhat predicting an event: in the Daśādhyāya-vinaya, Maudgalyāyana entered a village to beg for food. A householder's pregnant wife asked: "Is it a boy or a girl?" Maudgalyāyana said: "It is a boy." When she gave birth, it was a girl. Having been slandered, he asked the Buddha, and the Buddha said: "Originally it was a male fetus, but in the middle it changed into a female; Maudgalyāyana saw the former, not the latter, so it was not a false speech." Below, "the Vinaya..." next teaches uttering an oath. This refers to when there is an injustice, swearing an oath to clear it; the intention is to ask the Buddha to bear witness, hence it says "Namo Buddhāya" and so forth.