修習止觀坐禪法要 1.91

1.91

五者、一心分明。明見世間可患可惡，善識定慧功德可尊可貴。爾時應當一心決定修行止觀，心如金剛，天魔外道不能沮壞。設使空無所獲，終不回易，是名一心。譬如人行，先須知道通塞之相，然後決定一心涉路而進，故說巧慧一心。經云：「非智不禪，非禪不智。」義在此也。

The fifth is single-minded clarity. Clearly seeing that the worldly is to be deplored and detested, and skillfully recognizing that the merits of concentration and wisdom are venerable and precious. At that time, one should single-mindedly and decisively cultivate calming and contemplation, with a mind like a diamond, which heavenly Māras and non-Buddhists cannot frustrate or break. Even if one were to obtain nothing at all in vain, one would never turn back or alter [one's resolve]; this is called single-mindedness. For example, when a person travels, they must first know the features of open and blocked paths, and only then proceed with a resolute single mind upon the road; therefore it speaks of skillful wisdom and single-mindedness. A sūtra says: "Without wisdom there is no dhyāna; without dhyāna there is no wisdom." The meaning lies in this.