Indriyasaṁvarasutta
“Indriyasaṁvare, bhikkhave, asati indriyasaṁvaravipannassa hatūpanisaṁ hoti sīlaṁ; sīle asati sīlavipannassa hatūpaniso hoti sammāsamādhi; sammāsamādhimhi asati sammāsamādhivipannassa hatūpanisaṁ hoti yathābhūtañāṇadassanaṁ; yathābhūtañāṇadassane asati yathābhūtañāṇadassanavipannassa hatūpaniso hoti nibbidāvirāgo; nibbidāvirāge asati nibbidāvirāgavipannassa hatūpanisaṁ hoti vimuttiñāṇadassanaṁ. Seyyathāpi, bhikkhave, rukkho sākhāpalāsavipanno. Tassa papaṭikāpi na pāripūriṁ gacchati, tacopi na pāripūriṁ gacchati, pheggupi na pāripūriṁ gacchati, sāropi na pāripūriṁ gacchati. Evamevaṁ kho, bhikkhave, indriyasaṁvare asati indriyasaṁvaravipannassa hatūpanisaṁ hoti sīlaṁ …pe… vimuttiñāṇadassanaṁ.
Sense Restraint
“Mendicants, when there is no sense restraint, one who lacks sense restraint has destroyed a vital condition for ethical conduct. When there is no ethical conduct, one who lacks ethics has destroyed a vital condition for right immersion. When there is no right immersion, one who lacks right immersion has destroyed a vital condition for true knowledge and vision. When there is no true knowledge and vision, one who lacks true knowledge and vision has destroyed a vital condition for disillusionment and dispassion. When there is no disillusionment and dispassion, one who lacks disillusionment and dispassion has destroyed a vital condition for knowledge and vision of freedom. Suppose there was a tree that lacked branches and foliage. Its shoots, bark, softwood, and heartwood would not grow to fullness. In the same way, when there is no sense restraint, one who lacks sense restraint has destroyed a vital condition for ethical conduct. … One who lacks disillusionment and dispassion has destroyed a vital condition for knowledge and vision of freedom.