太子瑞應本起經 2.47

2.47

佛諸弟子皆故梵志，佛為諸弟子現神變化：一者飛行，二者說經，三者教誡。諸弟子見佛威神，莫不歡喜，作禮奉行。

The Buddha's disciples had all formerly been brāhmaṇas. The Buddha manifested spiritual transformations for the disciples: first, flying through the air; second, preaching the sūtras; third, giving admonitions. When the disciples saw the Buddha's spiritual majesty, there was none who did not rejoice, paying homage and practicing in accordance [with his teachings].