What is the role of karma in the wheel of becoming?

AN 6.63 states: "kamma is intention". In the Dependent Origination, intention (cetana) is first mentioned at nama-rupa (4th condition).

It is one of the greatest errors & corruptions to regard "sankhara" (2nd condition) as "kamma" because sankhara (in SN 12.2) is defined (per MN 44) as the in & out breathing (kaya sankhara); initial & discursive thought (vaci sankhara); and perception & feeling (citta sankhara). Bhikkhu Thanissaro explains this very well in the meditative examples in his book The Shape of Suffering.

Suttas, such as SN 14.12, show clearly that intention & kamma do not occur at sankhara (2nd condition), where sankhara is distracting thoughts & perceptions produced by ignorance (where ignorance, the 1st condition, includes the sensuality element or asava), as follows:

Bhikshus, dependent on the sensuality element [ignorance], perception of sensuality arises [sankhara]; dependent on perception of sensuality, sensual intention [nama-rupa] arises; dependent on sensual intention, sensual desire arises [craving]; dependent on sensual desire, sensual passion arises; dependent on sensual passion , sensual quest [attachment] arises; engaged in the quest of sensuality, the uninstructed worldling conducts himself [becoming] wrongly in these three ways—with the body, with speech and with the mind. SN 14.12

Note: the 'asava' ('outflows') are included within ignorance in MN 9.

Therefore, mental kamma or mental intention 1st comes into play at 'nama-rupa' (mind-body; 4th condition), namely, when ignorance takes control of the mind-body & the mind-body inclines (namati) towards pursing the ignorant urges & formations produced by ignorance & sankhara. About 'nama-rupa', SN 12.2 states:

Feeling, perception, volition (intention), contact and attention — these are called mentality. The four great elements and the material form derived from the four great elements — these are called materiality. SN 12.2; MN 9

For example, you are quietly meditating then a sensual urge suddenly spontaneously erupts. The sensual urge/energy is from ignorance (1st condition) & the distracting sensual thoughts & perceptions are sankhara (2nd condition). At this cross-roads, the mind & body (nama-rupa), if mindful, can choose/intend to ignore or calm the sensual urge & thoughts or, otherwise, if unmindful, can intend (4th condition) to follow the sensual urge & thoughts. This is the first occurrence of intention in the dependent origination, namely, at the 4th condition.

Then kamma (mental, verbal & bodily) becomes mature at "becoming" (bhava), as explained in AN 3.76. Note how there must be craving for kamma to fully occur.

Lord, this word, 'becoming, becoming' — to what extent is there becoming?

Ananda, if there were no kamma ripening in the sensuality-property, would sensuality-becoming be discerned?

No, lord.

Thus kamma is the field, consciousness the seed, and craving the moisture. The consciousness of living beings hindered by ignorance & fettered by craving is established in/tuned to a lower property. Thus there is the production of renewed becoming in the future.

In conclusion, meditation is required to comprehend dependent origination for oneself (rather than believe in unverified ideas of scholars). It is important to discern in meditation that the distracting thoughts & urges that spontaneously arise are not volitional or not intentional. Given these spontaneous urges (avicca; asava) & spontaneous thoughts & perceptions (sankhara) are not volitional, they cannot be "kamma" because kamma is intentional action (per AN 6.63).

"Sankhara Paccaya Vinnana" - Paticca-samuppāda

Karma causes the first thought moment of the next life. In other words, it determines where you are born next. Apart from that, good Karma causes pleasant experiences and bad Karma causes unpleasant experiences throughout the life.

Tipitaka translation version and reading study system are the main cause of your question. You can't see the answer by yourself because you never recite and memorize suttanta-pāli like the ancient buddhist people did, such as commentary teachers did.

Cause-saṅkhāra and effect-saṅkhāra

There are 2 main type of saṅkhāra words are using in tipitaka: cause-saṅkhāra, that cause effect-saṅkhāra arising, and effect-saṅkhāra, that depending on cause-saṅkhāra to arise.

Cause-saṅkhāra example from S.N. Nidānavagga Paṭiccasamuppādavibhaṅga sutta:

Saṅkhārā paccayā viññāṇaṃ.

Direct translation: Fabrications cause mind.

Alternative translation: Fabrications fabricate mind.

You can see above saṅkhārā is in the cause position of sentence.

Effect-saṅkhāra example from D.N. mahāparinibbānasutta:

handadāni bhikkhave āmantayāmi vo vayadhammā saṅkhārā appamādena sampādetha.

Behold now, bhikkhus, I exhort you: All compounded things[saṅkhārā] are subject to cease. Strive with earnestness.

You can see above saṅkhārā is in the effect position of sentence because buddha taught in S.N. Nidānavagga Paccayasutta:

viññāṇaṃ bhikkhave aniccā saṅkhatā paṭiccasamuppannā khayadhammā vayadhammā virāgadhammā nirodhadhammā. ime vuccanti bhikkhave paṭiccasamuppannā dhammā.

saṅkhārā bhikkhave aniccā saṅkhatā paṭiccasamuppannā khayadhammā vayadhammā virāgadhammā nirodhadhammā. ime vuccanti bhikkhave paṭiccasamuppannā dhammā.

avijjā bhikkhave aniccā saṅkhatā paṭiccasamuppannā khayadhammā vayadhammā virāgadhammā nirodhadhammā. ime vuccanti bhikkhave paṭiccasamuppannā dhammā.

Monks, mind are impermanent, produced by a combination of causes, arise on account of a cause, a wasting thing, a decreasing thing, a fading thing and a ceasing thing.

Monks, fabrications are impermanent, produced by a combination of causes, arise on account of a cause, a wasting thing, a decreasing thing, a fading thing and a ceasing thing.

Monks, ignorance is impermanent, produced by a combination of causes. Arise on account of a cause, a wasting thing, a decreasing thing, a fading thing and a ceasing thing. (Āsavā cause ignorance.)

Monks, this is called effects.

From above sutta, saṅkhatā (meaning: "effect is fabricated by causes") and vayadhammā is predicate of avijjā, saṅkhārā, and viññānaṃ. Because they are arisen by their causes. So the context of above sutta showing the condition of causes and effects to let the listener see avijjā, saṅkhārā, and viññānaṃ as effect-saṅkhāra like saṅkhārā word in mahāparinibbānasutta, above.

If you understand pāli's relation of saṅkhāra, like I have explained it above to you. You can see the role of karma.

Role of karma

Role of karma already defined in pāli, S.N. Nidānavagga paṭiccasamuppādavibhaṅgasutta, as cause-saṅkhāra:

Saṅkhārā paccayā viññāṇaṃ.

Direct translation: Fabrications cause mind.

Alternative translation: Fabrications fabricate mind.

You can search more more detail of karma's role by it's nature:

‘‘katame ca, bhikkhave, saṅkhārā? tayome, bhikkhave, saṅkhārā – kāyasaṅkhāro, vacīsaṅkhāro, cittasaṅkhāroฯ ime vuccanti, bhikkhave, saṅkhārāฯ

"And what are fabrications? These three are fabrications: bodily fabrications, verbal fabrications, mental fabrications. These are called fabrications.

You can notice all above saṅkhāras' explanations are causes, paṭiccasamuppādā, of their effects, paṭiccasamuppannā, by bhūmijasutta in the same cannon, S.N. Nidānavagga. This sutta show that "kamma is intention, cetanā, and intention is saṅkhāra", so in many sutta taught about kāya-saṅkhāra (kāya-kamma, kāya-sañcetanā, kāya-ducarita, kāya-sucarita, puññābhisaṅkhāra, apuññābhisaṅkhāra), vacī-saṅkhāra (vacī-kamma, vacī-sañcetanā, vacī-ducarita, vacī-sucarita, puññābhisaṅkhāra, apuññābhisaṅkhāra), citta-saṅkhāra (mano-kamma, mano-sañcetanā, mano-ducarita, mano-sucarita, puññābhisaṅkhāra, apuññābhisaṅkhāra, āneñjābhisaṅkhāra) by the same context as kamma [cause] of vipāka [resultants]. You can use my example pāli words ad search by yourself.

Also, according to that bhūmijasutta, viññāṇa, nama-rupa, saḷāyatana, phassa, and vedanā in the Dependent Origination, are vipāka of saṅkhāra, too. Because no one can say "while viññāṇa arising, there is no nama-rupa arising, no āyatana arising, no phassa arising, and no vedanā arising". So, in M.N. uparipaṇṇāsa, anupada sutta taught the simultaneous arising of them:

[155] Idha bhikkhave sārīputto vivicceva kāmehi vivicca akusalehi dhammehi savitakkaṃ savicāraṃ vivekajaṃ pītisukhaṃ paṭhamaṃ jhānaṃ upasampajja viharati . ye ca paṭhame jhāne dhammā vitakko ca vicāro ca pīti ca sukhañca cittekaggatā
ca phasso vedanā saññā cetanā viññāṇaṃ 1- chando adhimokkho viriyaṃ sati upekkhā manasikāro tyassa dhammā anupadavavatthitā
honti tyassa dhammā viditā uppajjanti viditā upaṭṭhahanti
viditā abbhatthaṃ gacchanti . so evaṃ pajānāti Evaṃ kirame dhammā ahutvā sambhonti hutvā pativentīti 1- . So tesu dhammesu anupāyo anapāyo
anissito appaṭibaddho vippamutto visaṃyutto vimariyādikatena
cetasā viharati . so atthi uttariṃ nissaraṇanti pajānāti tabbahulīkārā atthi tvevassa hoti.

“Again, bhikkhus, Sāriputta, overcoming thoughts and thought processes, the mind internally appeased in one point, with joy and pleasāntness born of concentration abides in the second jhānaThese things of the second jhāna such as internal appeas*m*nt, joy, pleasantness, one pointedness of mind, contact, feelings, perceptions, intentions, interest, resolution, effort, mindfulness, equanimity and attention, follow one after the other, to him. They rise, persist and fade with his knowledge. He knows, these things come to be and cause feelings to rise. When these things follow one after the other, he abides with a mind that does not settle, is not bound, is released and unyokedand is unrestricted. knows there is an escape beyond this. With much practise they come to him.

This sutta taught about jhāna, and jhāna is puññābhisaṅkhāra and apuññābhiaṅkhāra in A.N. ekādasakanipāta, aṭṭhakanāgarasutta. So simultaneous arising in anupadasutta referring to cause-saṅkhāra. However, pāli-student should use simultaneous arising with effect of the cause-saṅkhāra in the Dependent Origination, too, because when someone birth they must have viññāṇa, nama-rupa, saḷāyatana, phassa, and vedanā. Except asaññasatta-brahmma, arūpa-brahmma, and saññāvedayittanirodhasamāpatti-person, no one live without them, right?

There is no pāli error

But saṅkhāra in M.N. 44 cūlavedallasutta is not cause-saṅkhāra, so the pāli-student can not compare saṅkhāra in M.N. 44 cūlavedallasutta with saṅkhāra in bhūmijasutta and paṭiccasamuppādavibhaṅgasutta. So the fact is, it is not pāli's error".

Explanation of saṅkhāra in M.N. 44 cūlavedallasutta

M.N. 44 cūlavedallasutta taught about effect-saṅkhāra, because visākhā-upāsaka was anāgāmi-ariya, and dhammadinnā-therī was arahanta-ariya, and both ariya already ceased five kāmaguṇa attachment, so visākhā-upāsaka asked dhammadinnā-therī about jhāna which causes the cessation of five kāmaguṇa attachment. And jhāna causes the cessation of in-&-out breaths, directed thought & evaluation, and perceptions & feelings, too. Therefore dhammadinnā-therī answered:

Assāsapassāsā kho āvuso visākha kāyasaṅkhāro vitakkavicārā vacīsaṅkhāro saññā ca vedanā ca cittasaṅkhāroti.

"In-&-out breaths are bodily fabrications. Directed thought & evaluation are verbal fabrications. Perceptions & feelings are mental fabrications."

Because 4th jhāna causes the cessation of in-&-out breaths, 2nd jhāna causes the cessation of directed thought & evaluation, and saññāvedayitanirodhasamāpatti causes the cessation of perceptions & feelings [saññāvedayitanirodhasamāpatti translation: "the achievement to cease the perceptions & feelings"]. So in D.N. Dasuttarasutta, ten Ariyan methods of living, taught about bodily fabrications (kāya-saṅkhāra) are ceased by 4th jhāna. Also, bodily fabrications (kāya-saṅkhāra) use in ānāpanassati-jhāna method in mahāsatipaṭṭhānasutta, too. Both sutta enough to show that bodily fabrications in M.N. 44 cūlavedallasutta referring to effect-saṅkhāra.

Then, you will not do an reader error:

AN 6.63 states: "kamma is intention". In the Dependent Origination, intention (cetana) is first mentioned at nama-rupa (4th condition).

It is one of the greatest errors & corruptions to regard "sankhara" (2nd condition) as "kamma" because sankhara (in SN 12.2) is defined (per MN 44) as the in & out breathing (kaya sankhara); initial & discursive thought (vaci sankhara); and perception & feeling (citta sankhara). Bhikkhu Thanissaro explains this very well in the meditative examples in his book The Shape of Suffering.

Suttas, such as SN 14.12, show clearly that intention & kamma do not occur at sankhara (2nd condition), where sankhara is distracting thoughts & perceptions produced by ignorance (where ignorance, the 1st condition, includes the sensuality element or asava), as follows

So, I often say "Tipitaka translation version and reading study system are the main cause of your question. You can't see the answer by yourself because you never recite and memorize suttanta like the ancient buddhist people did, such as commentary teachers did."

Since it is all about the topic, one may find this useful as a guide:

Kamma: A Study Guide, by Thanissaro Bhikkhu (2000; 48pp./145KB) An overview of the Buddha's teachings on kamma (karma; intentional action).

The Karma of Questions As the author writes in the Introduction: "There's no such thing as a totally idle question. Every question, even the most casual, carries an intention." Since one's intentions shape the course of one's entire spiritual journey, learning to ask the right kinds of questions plays an essential role in any spiritual practice. This collection of essays explores the nature of questions in the Buddhist path. Essays include: Life Isn't Just Suffering, Opening the Door to the Dhamma, Questions of Skill, Freedom from Fear, Samsara, Samsara Divided by Zero, The Agendas of Mindfulness, De-perception, The Weight of Mountains, File Piles of Bricks, and "When you know for yourselves...". Available in various formats at dharmatalks.org. To request a free printed copy of this book, please write to: Metta Forest Monastery, PO Box 1409, Valley Center, CA 92082 USA.

The Road to Nirvana Is Paved with Skillful Intentions According to the basic principle of karma, our underlying intentions play a crucial role in determining the ultimate fruits of our actions. As the author explains in this essay, if we're genuinely interested in pursuing the goal of the Buddha's teachings, it's not enough that we act merely with good intentions; rather, we must learn, through honest self-reflection and association with virtuous and wise friends, to cultivate skillfulness in our intentions. A printed copy is included in the book Noble Strategy.

[Note: This is a gift of Dhamma and not meant for commercial purpose or other low wordily gains by means of trade and exchange.]