"Generally speaking, Zen teachers nowadays instruct people by setting up rules or using devices. believing that without devices they can't manage, behaving as if without them it's impossible to instruct anyone, they're unable to teach by simply pointing things out directly. To teach people [this way], unable to manage without devices, is 'devices Zen.'
"Others tell students pursuing this teaching that it's no good unless they rouse a great ball of doubt and succeed in breaking through it. 'No matter what,' they tell them, 'you've got to rouse a ball of doubt!' They don't teach, 'Abide in the Unborn Buddha Mind!' [but instead] cause people without any ball of doubt to saddle themselves with one, making them exchange the Buddha Mind for a ball of doubt. A mistaken business, isn't it!"
(Bankei Yotaku, tr. Peter Haskel)
"If the Buddha-Nature is seen, there will be no seeing of a nature in any thing."
(Nirvana Sutra, T12n374p521b3; tr Yamamoto)
"Neither cultivation nor seated meditation — this is the pure Chan of Tathagata."
(Mazu Daoyi, X1321p3b23; tr. Jinhua Jia)
“Don’t rashly seek the true Buddha;
True Buddha can’t be found.
Does marvelous nature and spirit
Need tempering or refinement?
Mind is this mind carefree;
This face, the face at birth."
(Nanyue Mingzan: Enjoying the Way, tr. Jeff Shore; T2076p461b24-26)