Visesato panettha saddhāpaññānaṃ samādhivīriyānañca samataṃ pasaṃsanti.
Ñ(IV,47): However, what is particularly recommended is balancing faith with understanding, and concentration with energy.
Balavasaddho hi mandapañño muddhappasanno hoti, avatthusmiṃ pasīdati.
Ñ: For one strong in faith and weak in understanding has confidence uncritically and groundlessly.
Balavapañño mandasaddho kerāṭikapakkhaṃ bhajati, bhesajjasamuṭṭhito viya rogo atekiccho hoti.
Ñ: One strong in understanding and weak in faith errs on the side of cunning and is as hard to cure as one sick of a disease caused by medicine.
Ubhinnaṃ samatāya vatthusmiṃyeva pasīdati.
Ñ: With the balancing of the two a man has confidence only when there are grounds for it.
Balavasamādhiṃ pana mandavīriyaṃ samādhissa kosajjapakkhattā kosajjaṃ abhibhavati.
Ñ: Then idleness overpowers one strong in concentration and weak in energy, since concentration favours idleness. 
Balavavīriyaṃ mandasamādhiṃ vīriyassa uddhaccapakkhattā uddhaccaṃ abhibhavati.
Ñ: Agitation overpowers one strong in energy and weak in concentration, since energy favours agitation.
Samādhi pana vīriyena saṃyojito kosajje patituṃ na labhati.
Ñ: But concentration coupled with energy cannot lapse into idleness,
Vīriyaṃ samādhinā saṃyojitaṃ uddhacce patituṃ na labhati, tasmā tadubhayaṃ samaṃ kātabbaṃ.
Ñ: and energy coupled with concentration cannot lapse into agitation. So these two should be balanced;
Ubhayasamatāya hi appanā hoti.
Ñ: for absorption comes with the balancing of the two.