Kāmañcete vitakkavicārā dutiyajjhāneyeva vūpasantā, imassa pana jhānassa maggaparidīpanatthaṃ vaṇṇabhaṇanatthañcetaṃ vuttaṃ.
Ñ(IV,155): Of course, applied and sustained thought have already been stilled in the second jhāna, too. However, this is said in order to show the path to this third jhāna and in order to recommend it.
Ñ: For when 'with the stilling of applied and sustained thought' is said, it is declared that the path to this jhāna is necessarily by the stilling of applied and sustained thought.
Yathā ca tatiye ariyamagge appahīnānampi sakkāyadiṭṭhādīnaṃ ‘‘pañcannaṃ orambhāgiyānaṃ saṃyojanānaṃ pahānā’’ti (dī. ni. 1.373; ma. ni. 2.133; saṃ. ni. 5.184; a. ni. 3.88) evaṃ pahānaṃ vuccamānaṃ vaṇṇabhaṇanaṃ hoti, tadadhigamāya ussukkānaṃ ussāhajanakaṃ, evameva idha avūpasantānampi vitakkavicārānaṃ vūpasamo vuccamāno vaṇṇabhaṇanaṃ hoti.
譬如在第三圣道（阿那含向）本不是舍断的然亦说「舍断身见等五下分结故」，当知如是而说舍断是赞叹的 [PTS 160]，是为了努力证得（第三圣道）者的鼓励的；如是此（第三禅）虽非止息的，但为赞叹亦说是寻伺的止息。
Ñ: And just as, although mistaken view of individuality, etc., are not abandoned in the attaining of the third Noble Path [but in the first], yet when it is recommended by describing their abandonment thus 'With the abandoning of the five lower fetters' (A.i,232),  then it awakens eagerness in those trying to attain that third Noble Path, — so too, when the stilling of applied and sustained thought is mentioned, though they are not actually stilled here [but in the second], this is a recommendation.
Tenāyamattho vutto ‘‘pītiyā ca samatikkamā vitakkavicārānañca vūpasamā’’ti.
Ñ: Hence the meaning expressed is this: 'With the surmounting of happiness and with the stilling of applied and sustained thought'.