Visuddhimagga IV-174

Kiñca bhiyyo, yathā dhenupago vaccho dhenuto apanīto arakkhiyamāno punadeva dhenuṃ upagacchati, evamidaṃ tatiyajjhānasukhaṃ pītito apanītaṃ, taṃ satisampajaññārakkhena arakkhiyamānaṃ punadeva pītiṃ upagaccheyya, pītisampayuttameva siyā.

更有什么说念与正知的理由呢？譬如正在哺乳的犊子，将它从母牛分开，但你不看守它的时候，它必定会再跑近母牛去；如是这第三禅的乐虽从喜分离，如果不以念与正知去守护它，则必然又跑进于喜及于喜相应。

Ñ(IV,174): What is more, just as a calf that follows a cow returns to the cow when taken away from her if not prevented, so too, when this third jhāna is led away from happiness, it would return to happiness if not prevented by mindfulness and full awareness, and would rejoin happiness.

Sukhe vāpi sattā sārajjanti, idañca atimadhuraṃ sukhaṃ, tato paraṃ sukhābhāvā.

或者诸有情是恋着于乐，而此三禅之乐是极其微妙，实无有乐而过于此，

Ñ: And besides, beings are greedy for bliss, and this kind of bliss is exceedingly sweet since there is none greater.

Satisampajaññānubhāvena panettha sukhe asārajjanā hoti, no aññathāti imampi atthavisesaṃ dassetuṃ idamidheva vuttanti veditabbaṃ.

必须由于念与正知的威力才不至恋于此乐，实无他法。为了表示这特殊的意义，故仅于第三禅说念与正知。

Ñ: But here there is non-greed for the bliss owing to the influence of the mindfulness and full awareness, not for any other reason. And so it should also be understood that it is stated only here in order to emphasize this meaning too.