Dilgo Khyentse Rinpoche explains in The Heart Treasure of the Enlightened Ones,
Chenrezig is a fully enlightened Buddha who in order to benefit beings takes on the form of a Bodhisattva. All the Buddhas have but one nature and their compassion is embodied in Chenrezig. As the embodiment of the compassion of all Buddhas Chenrezig is at the same time the source of all Buddhas and bodhisattvas since compassion is the very root of enlightenment.
Chenrezig is compassion itself in the form of a deity.
Chenrezig manifests in infinite forms, kings, spiritual teachers, ordinary men and women, sometimes as animals, mountains or even trees. Even a cool breeze on a scorching summer’s day is a manifestation of Chenrezig’s compassion.
Totally free from samsara, Chenrezig is always ready to help sentient beings and even his slightest movement, a hand gesture, a blink of his eyes, has the power to free us from samsara.
Om mani padme hum
Note: Dza Patrul Rinpoche Wrote Heart Treasure of the Enlightened Ones. Dilgo Khyentse provided the commentary.