大方廣佛華嚴經疏 50.13

50.13

二釋中，先總釋。同一無性，故得現成。妄性本虛，生元是佛，真性叵得，非今始成，故皆成也。

In the second, the explanation: first, general explanation. Being of the same absence of nature, they can be accomplished right now. The nature of delusion is fundamentally false, so sentient beings are originally Buddhas; the true nature cannot be attained [as a newly produced thing], so it is not just now beginning to be accomplished; hence all are accomplished.