The Mahayana Vijñapti Sutra (Volume 58)

As when a face appears in a mirror: if the mirror is neither clean nor clear, the facial image will not appear. When the mirror is clear and clean, and the face is turned towards it, the reflection appears. The reflection in the mirror neither feels nor thinks, yet it follows the movements of the person—bending, stretching, bowing, raising the head, opening the mouth, talking, joking, coming, going, advancing, halting—all manner of actions. The person outside the mirror, whether speaking or moving, is mirrored accordingly in the reflection.

The Buddha asked Bhadrapāla, "By whose power does the reflection in the mirror appear?"

Bhadrapāla replied to the Buddha, "It is the power of the person. Because the face exists, the reflection of the face appears in the mirror. The appearance of the reflection is identical to the appearance of the face. Whether the reflection is complete with all six faculties or not, it perfectly matches whether the person outside the mirror possesses all six faculties or not."