坐禪三昧經 2.22

2.22

答曰：「無也。婬欲不應是樂。何以故？若婬欲在內，不應外求女色，外求女色當知婬苦。若婬是樂，不應時時棄，若棄不應是樂。於大苦中，以小苦為樂也。如人應死，全命受鞭，以是為樂。欲心熾盛，以欲為樂，老時厭欲，知欲非樂。若實樂相，不應生厭。如是種種，因緣欲樂相，實不可得，樂失則苦。佛言：『樂痛應觀苦，苦痛應觀樂，如箭在體，不苦不樂應觀生滅無常。』是謂痛念止。」

The answer is: "It is not so. Rāga should not be [considered] pleasure. Why? If rāga were internal, one should not externally seek female beauty; in externally seeking female beauty, one should know that lust is suffering. If lust were pleasure, one should not abandon it from time to time; if it is abandoned, it should not be pleasure. In the midst of great suffering, one takes small suffering as pleasure. Just as a person condemned to death has their life spared and receives a flogging, and takes this as pleasure. When the lustful mind blazes, one takes desire as pleasure; in old age, weary of desire, one knows that desire is not pleasure. If it had the mark of true pleasure, weariness should not arise. Such various marks of pleasure from desire born of causes and conditions are truly unobtainable; when pleasure is lost, then there is suffering. The Buddha said: 'One should contemplate pleasant sensation as suffering; one should contemplate painful sensation as a dart in the flesh; one should contemplate neither-painful-nor-pleasant sensation as arising, perishing, and anitya.' This is called mindfulness of sensation."