[43] Which, on that occasion, is the power of concentration (samādhibala)?
That which, on that occasion, is stability of mind (citta), steadfastness, steadiness, non-wavering, non-distraction, the state of unwavering mentality, calm (samatha), the faculty of concentration (samādhindriya), the power of concentration, right concentration (sammāsamādhi) — this, on that occasion, is the power of concentration.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.