摩訶止觀 9.129

9.129

若得此意，但取法正，色相非正也。若專取色相者，魔變作相，泥木圖寫，皆應是佛。又如來示現自在無礙，何必一向作丈光？丈光形者，示同端正人耳。佛遍示所喜身、遍示所宜身、遍示對治身、遍示得度身；師僧、父母、鹿馬、猨猴，一切色像隨得見時，與法門俱發。又能增長本之善根，乃名「念佛三昧」（云云）。

If one grasps this meaning, one takes only the Dharma as correct, whereas physical marks are not what is correct. If one exclusively grasps physical marks, Māra can transform into these marks, and clay, wood, paintings, and drawings should all be buddhas. Furthermore, the Tathāgata manifests with sovereign freedom and unimpededness; why must he unvaryingly appear as a one-fathom radiance? The form of a one-fathom radiance is merely manifested to accord with a handsome human being. The Buddha everywhere manifests the body one delights in, everywhere manifests the body that is appropriate, everywhere manifests the body for antidotes, and everywhere manifests the body for attaining deliverance: whether masters and monks, parents, deer and horses, or monkeys, whenever any form or image is seen, it manifests together with a Dharma gate. Furthermore, if it can foster one's original wholesome roots, it is only then called the 'buddha-mindfulness samādhi' (and so on).