瑜伽論記 11.280

11.280

言鹿、牛、馬、象者，有釋：鹿居山藪故喻獨覺，牛遲、馬疾，喻彼聲聞有鈍、有利。象，喻菩薩。基師云：喻四涅槃，象喻無住涅槃，餘三無導今不以義准。謂鹿始終常居山靜，喻本來淨。牛有角故，喻有餘依。馬無角故，喻無餘依。

Regarding "deer, ox, horse, and elephant": An explanation states: The deer resides in mountain thickets, hence it illustrates the pratyekabuddha; the ox is slow and the horse is swift, illustrating that those śrāvakas have dull and sharp faculties; the elephant illustrates the bodhisattva. Master [Kui]ji says: They illustrate the four nirvāṇas; the elephant illustrates the non-abiding nirvāṇa. The other three have no commentary [by Xuanzang], and now I do not infer them by reasoning. It means that the deer always resides in mountain tranquility from beginning to end, illustrating original purity. Because the ox has horns, it illustrates [nirvāṇa] with remainder. Because the horse has no horns, it illustrates [nirvāṇa] without remainder.