The Mahānidāna Sūtra (Sūtra on Great Conditions and Skillful Means), the Ninth, from the Dīrgha Āgama

Original text: 云何二入处。无想入。非想非无想入是为。阿难。此二入处。或有沙门婆罗门言。此处安隐。为救为护。为舍为灯。为明为归。为不虚妄。为不烦恼。阿难。若比丘知二入处。知集知灭。知味知过。知出要。如实知见。彼比丘言。彼非我。我非彼。如实知见。是为二入。 

Explanation: What are the two bases of entry? The base of entry into the sphere of neither-perception-nor-non-perception and the base of entry into the sphere of no perception—these are the two bases of entry. Ānanda, regarding these two bases of entry, some śramaṇas and brāhmaṇas declare them to be a place of peace and security, a place of rescue and protection, a dwelling, a place of the bright lamp, a place of light, a place of refuge, a place that is not false, a place without afflictions. Ānanda, if bhikṣus know these two bases of entry, knowing their arising and cessation, knowing their flavor and faults, and knowing the essential way to transcend them, and realize them as they truly are, those bhikṣus will say: "These two bases of entry are not me, and I am not the two bases of entry." Realizing and seeing this truth as it really is—these are the two bases of entry. 

Original text: 阿难。复有八解脱。云何八。色观色。初解脱。内无色想。观外色。二解脱。净解脱。三解脱。度色想。灭有对想。不念杂想。住空处。四解脱。度空处。住识处。五解脱。度识处。住不用处。六解脱。度不用处。住有想无想处。七解脱。灭尽定。八解脱。阿难。诸比丘于此八解脱。逆顺游行。入出自在。如是比丘得俱解脱。尔时。阿难闻佛所说。欢喜奉行。 

Explanation: Ānanda, there are also the eight liberations. What are the eight liberations? The first liberation is when the mind has perceptions of form and craving for form, one contemplates the impurity of form; upon realizing the impurity of form, the mind attains liberation. The second liberation is when the mind has no perceptions of form internally, one contemplates the impurity of external form; upon realizing the impurity of form, the mind attains liberation. The third liberation is liberation attained when both body and mind are pure. The fourth liberation is transcending perceptions of form, extinguishing perceptions opposed to form, neither perceiving form nor having other miscellaneous perceptions, abiding in the concentration of the sphere of infinite space, and attaining liberation. The fifth liberation is passing beyond the sphere of infinite space, abiding in the concentration of the sphere of infinite consciousness, and attaining liberation. The sixth liberation is passing beyond the sphere of infinite consciousness, abiding in the concentration of the sphere of nothingness, and attaining liberation. The seventh liberation is transcending the sphere of nothingness, abiding in the concentration of the sphere of neither-perception-nor-non-perception, and attaining liberation. The eighth liberation is abiding in the cessation of perception and feeling (saṃjñā-vedita-nirodha-samāpatti) and attaining liberation. Ānanda, regarding these eight liberations, whether the bhikṣus enter them in sequential order or in reverse order, they are at ease in entering and emerging from concentration. Such bhikṣus have fully realized all eight liberations and are called arhats liberated in both ways (ubhayatobhāgavimukta), fully endowed with liberating wisdom and the four dhyānas and eight concentrations.