References – SN 35.135: The Opportunity 
Readings by Ajahn Pasanno:
Sutta: SN 35.127, Saḷāyatanasaṁyutta, “Bhāradvāja.”
Sutta: SN 35.135, Saḷāyatanasaṁyutta, “The Opportunity.”
Sutta: SN 35.153, Saḷāyatanasaṁyutta, “Is There a Method?.”
Sutta: SN 35.155, Saḷāyatanasaṁyutta, “A Speaker on the Dhamma.”