佛說觀佛三昧海經 6.22

6.22

The Buddha told the great assembly: 'The Buddhas, the Tathāgatas, enter the place of emptiness and tranquility, and through the samādhi of liberation they are sovereign according to their wish; there is neither real nor transformed. Why is this? The Buddha-mind is empty and tranquil, and further enters the samādhi of the radiant king of empty and tranquil liberation. Through the power of this concentration, the Buddhas, the Tathāgatas, manifest boundless bodies. The boundless body is sarvajña; sarvajña is called the unattached samādhi. On account of the unattached samādhi, the Tathāgatas manifest walking: whether manifesting begging for food, or manifesting walking meditation. These two dharmas abundantly benefit sentient beings. If there are sentient beings who, when the Buddha is in the world, see the Buddha walking, with every step they see the thousand-spoked wheel mark and eradicate extremely grave, evil offenses of a thousand kalpas. After the Buddha has left the world, those who, in samādhi and right meditative absorption, imagine the Buddha walking also eradicate extremely grave, evil karma of a thousand kalpas. Even if they do not imagine his walking, those who see the Buddha's footprints or see an image walking also, with every step, eradicate extremely grave, evil karma of a thousand kalpas.'