佛說觀佛三昧海經 4.16

4.16

「云何觀如來面門光明？其光白色猶如寶山內外俱淨，於寶山內無量化佛真金精色。時諸化佛面門出光，其光五色遍照十方入諸佛面門。此相現時，行者行住坐臥，恒聞如來說四念處（身、受、心、法），并說境界令行者聞。聞已憶持閉目思惟，此光力故即得四念處法。時十方佛及釋迦文，於三昧中各申右手摩行者頂，而作是言：『善哉善哉，善男子！汝能真實行念佛定。』如是觀者名為正觀，若異觀者名為邪觀。

"How does one contemplate the light of the Tathāgata's mouth? Its light is white, resembling a jeweled mountain, pure both within and without. Within the jeweled mountain are immeasurable transformation Buddhas of pure refined golden color. At that time, light emerges from the mouths of the transformation Buddhas; its light is of five colors, shining everywhere across the ten directions and entering the mouths of the Buddhas. When this mark appears, whether walking, standing, sitting, or lying down, the practitioner constantly hears the Tathāgata expound the four applications of mindfulness (body, feelings, mind, and dharmas), and expound their cognitive objects so that the practitioner hears them. Having heard them, they retain them in memory, close their eyes, and contemplate them; through the power of this light, they immediately attain the dharmas of the four applications of mindfulness. At that time, the Buddhas of the ten directions and Śākyamuni each extend their right hand during samādhi, stroke the practitioner's head, and say: 'Excellent, excellent, good man! You are truly able to practice the concentration of mindfulness of the Buddha.' Such contemplation is called right contemplation; if one contemplates otherwise, it is called wrong contemplation.