Visuddhimagga IV-195

Tattha kiñcāpi ayaṃ upekkhā heṭṭhāpi tīsu jhānesu vijjati.

虽然此舍在下面的三禅中也存在，

Ñ(IV,195): Herein, this equanimity exists in the three lower jhānas too;

Yathā pana divā sūriyappabhābhibhavā sommabhāvena ca attano upakārakattena vā sabhāgāya rattiyā alābhā divā vijjamānāpi candalekhā aparisuddhā hoti apariyodātā, evamayampi tatramajjhattupekkhācandalekhā vitakkādipaccanīkadhammatejābhibhavā sabhāgāya ca upekkhāvedanārattiyā appaṭilābhā vijjamānāpi paṭhamādijjhānabhedesu aparisuddhā hoti.

譬如日间虽亦存在的新月，但为日间的阳光所夺及不得其喜悦与自己有益而同类的夜，所以不清净不洁白，如是此中舍之新月为寻等敌对法的势力所夺及不得其同分的舍受之夜，虽然存在，但在初等三禅中不得清净。

Ñ: but just as, although a crescent moon exists by day but is not purified or clear since it is outshone by the sun's radiance in the daytime or since it is deprived of the night, which is its ally owing to gentleness and owing to helpfulness to it, so too, this crescent moon of equanimity consisting in specific neutrality exists in the first jhāna, etc., but it is not purified since it is outshone by the glare of the opposing states consisting in applied thought, etc., and since it is deprived of the night of equanimity-as-feeling for its ally;

Tassā ca aparisuddhāya divā aparisuddhacandalekhāya pabhā viya sahajātāpi satiādayo aparisuddhāva honti.

因彼等（三禅中的舍）不清净，故俱生的念等亦不清净。犹如日间不明净的新月一样。

Ñ: and because it is not purified, the conascent mindfulness and other states are not purified either, like the unpurified crescent moon's radiance by day.

Tasmā tesu ekampi ‘‘upekkhāsatipārisuddhi’’nti na vuttaṃ.

所以在彼等下禅中，连一种也不能说是「舍念清净」的。

Ñ: That is why no one among these [first three jhānas] is said to have purity of mindfulness due to equanimity.

Idha pana vitakkādipaccanīkadhammatejābhibhavābhāvā sabhāgāya ca upekkhāvedanārattiyā paṭilābhā ayaṃ tatramajjhattupekkhācandalekhā ativiya parisuddhā.

可是在此（四禅中）业已不为寻等敌对法的势力所夺，又获得了同分的舍受的夜，故此中舍的新月极其清净。

Ñ: But here this crescent moon consisting in specific neutrality is utterly pure because it is not outshone by the glare of the opposing states consisting in applied thought, etc., and because it has the night of equanimity-as-feeling for its ally.

Tassā parisuddhattā parisuddhacandalekhāya pabhā viya sahajātāpi satiādayo parisuddhā honti pariyodātā.

因舍清净故，犹如洁净了的月光，则俱生的念等亦得清净洁白。

Ñ: And since it is purified, the conascent mindfulness and other states are purified and clear also, like the purified crescent moon's radiance.

Tasmā idameva ‘‘upekkhāsatipārisuddhi’’nti vuttanti veditabbaṃ.

是故当知只有此第四禅称为「舍念清净」。

Ñ: That, it should be understood, is why only this jhāna is said to have purity of mindfulness due to equanimity.